Baccano and Durarara. DRRR(Durarara) is by the same guy who did Baccano!
Kara no Kyoukai (Highly complicated, also has tons of gore, and the 3rd movie has [censored] scenes and
7th has something similar as well, so beware!)
Code Geass
If you like Fate/Stay Night i highly suggest you check out its visual novel, as it has the full story and is MUCH better than the anime. KnK is done by the same guy(the novels), but the animation was by ufotable, and unlike F/SN anime, KnK(Kara no Kyokai) is a masterpiece. Also check the Tsukihime visual novel, again, by the same guy(Nasu Kinoko). Tsukihime anime? HAHAHAHA NOPENOPENOPE! Well ok it has one, but its so horrible fans outright deny its existence. I believe its now bloody obvious how much of a fan(boy) i am for Nasu's works, but seriously, when you get the time, check his stuff out~
Note that Fate/Zero, the animation of the prequel novels done by Gen Urobuchi, is coming out this year and is also by ufotable, so hopes for it being awesome as KnK are high, look forward to it~
Also, there's a comedy only OVA called Carnival Phantasm ongoing ATM, its a crossover between Tsukihime and Fate/Stay Night, check it out after seeing the other stuff.
Steins;Gate, one of the more awesome anime this year, definitely check it out.
Mahou Shoujo Madoka Magica/Puella Magi Madoka Magica, don't let its cuteness fool you, its a brilliant series with a highly dark take on the magical girl genre. Definitely worth watching.
Level E. Just. Watch. It. NOW. I won't spoil anything, just note that as you watch it you will be laughing your ass off, and may potentially die due to the hilarity. Plus its quite short.
Nichijou. Another comedy anime, worth watching.
Bakemonogatari and Katanagatari are worth watching as well. Both are by the same person. Also, a sequel series to Bakemono (Nisemonogatari) and a prequel movie (Kizumonogatari) are coming out, in 2012 i believe.
Mawaru Penguindrum, WATCH IT NOW.
Also, try Katekyo Hitman Reborn. Don't let the first 20 or so episodes give you the wrong impression, it evolves into a kickass action series down the line.
Jesus i have too many to suggest, UM, lets see.
Usagi Drop, its a slice of life feel good anime.
Ano Hana, its apparently quite good, and is a drama regarding a group of friends.
Dantalian no Shoka, something about a guy inheriting a girl who is the key to a library or something, WATCH IT.
The World God Only Knows, great manga and anime about a guy who hates real life girls, and yet is forced to make them fall in love with him due to a certain contract with a devil.
Baka to Test to Shoukanjuu/Ni. A hilarious comedy series, the Ni part is the sequel.
Deadman Wonderland. A dark and gory series about a 14 year old kid who's convicted for apparently annihilating all his classmates.
SENGOKU BASARA. Motherfucking SB, its a kickass series based on the Sengoky period in Japan. Expect awesome fights, MANLINESS and gundams.
Tengen Toppa Gurren Lagann. YOU CAN'T NOT WATCH THIS. It has fucking EVERYTHING, romance, comedy, kick ass action etc.
Panty and Stocking with Garterbelt. Just watch it.
Gundam 00/Season 2/Awakening of the Trailblazer. A pretty swell mecha series, worth watching.
Eureka Seven, another mecha series with heavy romance elements.
C: The Money of Soul and Possibility Control. Imagine Pokemon, but more kickass, serious, and with money being the main theme.
OK I AM DONE NOW HOPE YOU ENJOY THIS
Just have one last thing to say, don't restrict yourself to certain genres, otherwise you will miss the other gems out there. I can't force you or anything, its just a suggestion. Try other stuff out as well~