RJ 17 said:
But what's this Puella Magi Madoka Magica about? I've never even heard of this one.
As the name - basically something along the lines of Magical Girl Madoka - would imply, its a show about magical girls. Nothing like Sailor Moon or Card Captors. It is an amazing show that I was glad I got into. It fairly quickly gets dark, and from then only darker. Saying much more would be spoilers, but its good. Nobody I have ever run into online or offline would say otherwise.
As for other suggestions in this thread, I'll only comment on what I've seen so far.
Darker than Black: Is great. A brief synopsis of lore, and not plot, is that... 40? years ago two 'gates' - areas of the world where physics ceased to work properly, put simply - opened. One in Brazil called Heaven's gate, and one in Tokyo called Hell's gate. Around this same time 'Contractors' and 'Dolls' began appearing. Contractors are granted superhuman powers in return for an obesience/renumeration - the exact translation I've found differs from translator to translator. But basically, they feel compelled to do something like smoke, drink, flip someone's shoes upside down, sleep, play chess - any random task - as if it were an addiction, near immediately after they use their power. Dolls are emotionless people with no personality, who obey their masters orders, and have the ability to send a spiritual scout out through a specific medium. The plot centres around a Contractor and Doll named Hei and Yin, and the politics of the world in which they live in regards to their existence. Season one feels like its just messing around for a bit with no plot, but at the end it all comes together in a pretty straightforward and understandable way, with a slight twist of course. Season 2... Watch the OVAs first, as they are intermediary and required to make sense of season 2. Even then the end is quite out there, with not a lot truly explained and largely left up to interpretation. It kinda foreshadows what's going to happen, then has it happen - but doesn't say exactly what happened. Its kinda annoying and a lot of guesswork, but its still possible to take a reasonable guess at most things.
Stein's Gate: Based of a visual novel of the same name, the story centres around the invention of a time machine by a rather odd group. This creation leads them to be hunted by another organisation trying to make a time machine. Saying much more would be spoilers. I found the first episode alright, then the next four or so really annoying, as the main character continually fails to arrive at the obvious conclusion that he has time travelled, and acts like a complete and utter blathering idiot. After that though it becomes good, as things take a more serious turn and the actual plot begins. Its worth watching the whole way through, not giving up near the start 'cause it doesn't seem great.
Tengen Toppa Gurren Lagann: An entertaining anime for those that don't really want to put a ton of thought into things. Two main story arcs, but basically a mecha anime that is light hearted, funny, and empowering. Its also highly ridiculous and things get to a "So unreal its funny" stage near the end of the second half of the anime. Saying exactly what would ruin some awesome moments, but logic and seriousness fly out the window for this anime, but it does it well, and that makes it brilliant in its own way.
Accel World: Starts off fairly interesting. It kinda reverses the general dynamic whereby, in this anime, the hero and heroine are kinda the assholes of the story. The hero is also fat, short, and unattractive. Its interesting, and I like a lot of the ideas in the anime, and the technology, though it doesn't seem quite as polished {Maybe not the right word in this case, but it feels like its missing something} as the rest of them. Its a different kind of story. The second half of the season, however, reverts the original paradigm and the hero and heroine become the nice guys as opposed to the assholes. Kinda disappointing, but it works. Worth a watch, but if you get to four/five episodes in and don't enjoy it I'd probably stop.
Sword Art Online: The first half of the season is great. It deals with some serious themes, some not so serious themes too. It has happy moments, sad moments, glorious action moments, and peaceful everyday moments. Best way to describe it is "What if we lived in a videogame". The SECOND half of the season is utterly crap. I don't blame the author for this, as reading the light novels it was fairly decent - though it wasn't as good as the first half. The anime though... Rushes far too much. The first two episodes of the second half of the season are fine, but after that it skips a lot of the light novel to try and build up to the light novel's more epic moments, then gives the epic moment 2 minutes of screentime to build towards the next epic moment. Its a lot of buildup, and never any payoff. Its really disappointing, compared to the light novel where I jumped out of my seat screaming at some of the throwbacks to the first arc. Season two is set to be epic if they make it though.
Magi; The Labyrinth of Magic: In the end I'll say I liked it. Its different in feel to most other things I've watched. Its enjoyable, and largely light hearted - though there are some dark points too. I can't bring myself to wholeheartedly recommend it, but I can't say its bad either. I liked bits and pieces from it, and found other bits and pieces kind of boring, but overall I liked it and am awaiting 'Magi: The world of Magic' when it comes out.
Mouretsu Kaizoku: Not at all what the name would suggest. Translated to English its "Bodacious Space Pirates", making it sound kinda like Highschool DxD in space with some piracy on the side. Not at all what its about. Its a light hearted, well made story about a young group of girls who are originally part of a school yatch club [Only for the first few episodes, which are the less interesting of the anime], but a few of which come to man pirate vessels in a world where piracy isn't really piracy - its boarding a ship that has called you out to 'raid' it, putting on a show to act like pirates, being given willingly people's valuables, and then flying off whilst everything is replaced by an insurance company. Technically they're all privateers too, seeing as the main pirates have letters of marque, which are a major plotpoint in the series. True piracy comes in a lot later, and begins to expand the universe a lot more. I'm hoping for a sequel series. Its well made, light hearted and enjoyable, and not at all what the name may suggest. I'd put it as more shoujo that shounen anime, though its enjoyable for all IMO. Just... watch it. [BTW: Shounen = young boy, Shoujo = young girl]