Dragon Age, NHL, EA Sports MMA, Command & Conquer, Tiger Woods PGA, Army of Two, Crisis, Dead Space, SimCity (and all Sim games, actually), Need for Speed, Madden, SSX, Transformers, Alice, Spore, Portal (boxed retail copies were distributed by them, Valve controlled Steam sales), Bejeweled, Shank, Skate, Rockband, Dante's Inferno, Mirror's Edge, Left 4 Dead (same deal as with Portal) and more, but that's no big deal I suppose.
Dreamcast died because SEGA withdrew from the race on their own accord, not due to lack of third-party developer support.
At the time, management changed in the company and the newly-chosen CEO decided not to support the console post-release anymore - the console still got a good few AAA titles, for example Unreal Tournament, Quake III Arena (actual Quake III Arena that was compatible with the PC version, not the spunk the PS2 got), Shenmue, Bust-a-Move, Capcom vs. SNK, DDR, Dead or Alive 2, Fighting Force, GTA 2, Guilty Gear and many, many more.
The system may have failed big time sales-wise, but not library-wise - there's a selection of games for it, especially considering its short lifespan.