Voice communication. <- this has changed many games from being immersive to being brag fests and ego boosting or basically just too much goofing around/nonsensical chat by immature kids. VC = sore ears. That, and raiding in MMOS actually used to be fun and challenging before VC. Now you just gather up a bunch of lazy goofs and throw instructions at them. Watch half of them die, and the others obey and you win 100% of the time.
Nintendo Wii. It was a nice attempt at something new but it's just too different from playing with a real controller. Not fun imo.
Vibrating controllers. This function is in almost every game now, and it eats through battery power like... well you get the idea yeah? It's also annoying and throws off your precision when aiming or driving etc.
Modern day Graphics. Yes you heard me! I don't want pac-man graphics but, now-a-days too much money, time and effort is going into making the games pretty. Games don't need to look nice, they need to play nice first and foremost! Once they're fun to play, make the graphics as pretty as you want! I'm looking at you, video games with 3-9 hour campaigns! No excuse for that!
Clones. Yes clones! Games that try to almost exactly copy another game, hoping to win out on the cash flow, but fail! These are such a waste of money.
A recent example I've experienced:
TimeShift < Half-Life (You get a 'well-known' physicist in a super suit, and you shoot stuff in 1st person mode... in both games).
There are so many others, but I think I've contributed enough to the thread, that and my brain is starting to hurt :O