So. Madoka. It's a show. I'll say things I liked about Madoka, things I didn't like about Madoka, some nitpicks, then summarize my thoughts in a nutshell. Let's go on with this review.
Things I Liked
Art Style: One of the things that's really cool about Madoka is the jarring difference in art style between the show itself and the "Witch's Realm" (for the lack of a better term). The vanilla show itself is done in a very standard anime style. Nothing really remarkable there, but... It's serviceable. (Though, it kinda bugs me that the characters' faces are all rather... Boxy. But that's not really anything major.) However, the really cool part for me is how... eerie the shift in art-styles is. It adds this subtle level of creepiness which, to me, is really nicely done. And since the Witches represent the darkness in the world... I find it extremely fitting that the art style reflects that as well. So major props on that front.
Character Roles: To me, it felt that all the characters were used... Effectively. All the characters played the role that they were supposed to be well. Kyuubey is a good creepy... Thing that is more antagonistic in nature. Madoka plays the part of the protagonist well. Homura does a good job being the mysterious student. Mami does a good job being the mentor. All these roles were played out... Effectively.
Soundtrack: I may not be a fan of the actual songs themselves, in the sense that I wouldn't want to go around working, listening to the OST on my iPod... But the soundtrack of Madoka is extremely good. The songs fit really well with their respective scenes, and thematically are very nice. I may not like the songs, but I can definitely appreciate the fact that it is very well composed.
Consistency With Internal Logic: This is kind of a mouthful to say, certainly. But one really good thing about Madoka is that all the important concepts regarding magic, powers, and the universe are all (eventually) explained and are consistent with each other. The origin of witches? Explained. The reason Kyuubeys do this? Explained. The purpose of Soul Gems? Explained. It's really good that this is all explained, as this resulted in another good thing, which was a lack of major plot holes or inconsistencies.
Ending: The ending to me was quite well done: It fits as well as it can in the Madoka setting, with it being bittersweet, but still leaving a relatively "happy" ending for most of the characters involved. (Well. Except Sayaka. She's still screwed.) I found the fact that Homura uses Madoka's bow and arrow and still has her hair ribbon to be quite touching. That was sweet. I liked that.
Things I Disliked
The "zomg so edgey" Syndrome: Yeah... For a series that's trying to be more dark... It honestly didn't do such a good job. To me, it felt like it relied too much on shock, and as a result, the resulting world feels rather phony. Like, to me, a well constructed dark world would be done in one of two ways: The world that the characters are in feels like a world that our world could become, or the world appears to be fine, but in fact has many subtle things wrong with it. And, to me, the Madoka universe just doesn't do either of those. As a result, it feels... quasi dark? But, it also doesn't really feel dark enough, in my opinion. Unfortunately, Madoka goes down the route of "zomg dark and edgey, let's have people die", and to me, it felt really... Forced. This leads, unfortunately, to another problem...
Lack of Sympathy/Empathy: I may sound quite mean and not caring here but... By the time Sayaka and Kyoko died, I was like... Meh. To me, Madoka plays the "death" card way too much. Too many characters died in too few episodes for me to really care about their deaths. Sure, I understand that the deaths are necessary to move the plot forwards, and to make sure that Madoka becomes that supreme being at the end, but... It felt like their deaths were rather cheap, and to me, it lacked any emotional resonance.
Lack of Consistant Character Growth: I may have liked the roles that the characters played in Madoka, but... To me, it felt like most of the characters were extremely weird in their character development. Like... Most of the characters, in terms of personality, changed in a very erratic manner. For example, Sayaka went from a person who is extremely driven to succeed in her goals to "zomg angst angst". Kyoko was a girl who was really brashy and driven to succeed, doesn't really care about others... And all of a sudden she just becomes self-sacrificing against Sayaka's witch? And... Yes, I know that the shock of finding out the truth about Soul Gems would have drastically affected her, but... It still seems like the shift from Personality A to Personality B is too sudden. Homura, luckily, is an exception to that, as we do see her grow and mature as a character throughout. And I liked that we got to see growth in her character in a consistent manner.
Story Twists: Like I mentioned earlier, I felt like Madoka relied too much on shock twists. For example, the whole Homura is a time traveler twist felt really out of the blue (though, it does work in the context of the story, don't get me wrong). Kyuubeys wanting the whole magical girl/witch conflict to gather energy? Again, feels like a twist that's meant to shock. But that is only the first half of the problem I had. The other issue I had with the Madoka twists is that they were too predictable. Like... For example, Mami's death? It was pretty obvious to me that that was coming. Sayaka becoming a witch? Also pretty obvious that it was coming. So, for me, it feels kind of lame that the story doesn't have any twists which were subtly foreshadowed, and that I can come back from a future watching and be like "Oh, that's cool, how did I not notice that before?" There are things that I can appreciate from a future watching (such as Homura's actions throughout the show make sense now that we know that she's looping this over and over), but... That's not really a foreshadowy twist that I can appreciate.
Story Arcing: This one is much more of a "this is something I want" opinion, but... Since it's a review, I can include it anyways. But to me, it felt like Madoka lacked a central focus "arc" to have the entire story about. And... This bugged me, because there just seems like there is so much potential in the Madoka universe to do a centralized story arc. Yes, I know that the episodes are leading towards Madoka learning about the dark dangers of becoming a magical girl, and the whole conclusion of her rewriting the universe, but... It feels like Madoka would have benefited from some sort of centralized focus. The whole conflict with Walpurgisnacht feels more like a background event, rather than something that is important to lead towards. To kind of analogize it, it feels like I could disconnect each episode, and still make sense of what was going on, since there isn't really a large overarching grand story to Madoka. And, to me, it feels like Madoka would be a good story to have that type of large overarching story.
Minor Nitpicks
The OP: The OP ceases to really be fitting after Ep 4. I think that another OP would have been better after that point. Like, sure, I get that they're trying to be deconstructive, but... Still. By that point, people realize that. They changed the ED at that point, so... Why not the OP? (And yes, I know that the lyrics are meaningful, but still...)
Lack of Magical Girl Fights: I was excited when I saw Sayaka and Kyoko fighting in Episode 6. I thought that this could be a direction that they go down: Fighting magical girls that are willing to kill each other to defeat witches, and in turn, become witches themselves. But... No. They didn't go down that route. And also, it seemed that there were a lack of fights with witches themselves. Like... I think of all the episodes, there were only fights with witches in about... Half the episodes? Which, to me is a little strange, though, I can understand why they do it.
It Takes 12 Episodes for Madoka to Become a Magical Girl The show is called Puella Magi Madoka Magica. Yet it takes her the entire show to actually become a magical girl. That's just lame, show name. That's just lame. I understand why it's done, but still... Don't call your show about Madoka being a magical girl when she isn't a magical girl for pretty much the entire show. >_>
Mami uses guns, and guns are a lame weapon.
Overall
All in all... Madoka isn't a bad show, despite my long list of criticisms. It's a perfectly good show, but... It just feels lacking to me in many ways. The "dark" premise feels too shallow, and... Not well done. Many of the story twists feel like they are done for "shock" value, and as a result, it detracts me from enjoying it. The world of Madoka itself feels like so much more could be done with it, but... It just fails to live up to that potential. All in all, would I recommend watching Madoka? I guess I would? But, it certainly wouldn't be a heartily recommended show by me for others to watch.