I have read some doses of seinen manga, also a little in the other popular shonen, but honestly there are so many chapters it seems sort of pointless to start reading/wathcing them now.
Naruto (manga + anime)
One Piece (manga + anime)
Bleach (Anime + manga - last arc)
Noblesse (manga)
The Breaker : New Waves (manga)
Attack on titan (only anime)
Psyren (manga => I know it's finished but it rocked )
Naruto, Fairy Tail, Claymore, King of Hell, Deadman Wonderland, just started one Piece again, (after only making it to like chapter 75 as a kid) and it's amazing, currently at the CP9 arc
Recently I 've just been reading Bleach and "The Breaker- new waves" (a Manhwa, to be exact).
For OP I want to wait in order to spare for the anime > though it's a bit tough bc I'm sooo curious -