Disappointing games:
fly! - garbage
counterstrike - overrated
silent hunter 2 and desroyer command - no dynamic campaign, crappy ship animations, bad online gameplay
interstate 82 - jesus christ this was a baaaaaaaaaad game
i am no longer buying any electronic arts games - they are bastards
new games generally suck because the developers are hoping to cash in on the lastest society trend (for example: nfs underground, lord of the rings, yu-gi-oh), when gaming was for hardcore geeks they had to make good games or people would go back to dungeons and dragons and axis and allies
developers of games like HL2 and DOOM3 have a lot of pressue on them to make a great game, i don't think this formulated approach always works to create a classic like the first game was.