Just two things:

Call of Duty

no ethernet port on Wii

- Downloadable content. Especially they purposefully leave things out of the game so they can sell it as DLC.

- Call me backwards thinking if you want; but digital distribution. I'm a fan of owning physical disks rather then digital copies. Plus the disk versions cost the same usually; if digital copies were cheaper maybe I'd buy them.

- Okay I know it started last gen; but this gen they've really milked the music games. Guitar Hero, Rock Band, DJ Hero, Wii Music, plus countless low budget games trying to get in on the music game fad.

I'll only list out stuff that's about the actual games, nothing about the media (e.g. bitching about "casuals," bullshit reviews, etc).

DLC.
Reasons are all over the thread, but basically, we're being charged extra in order to play the "full game." Screw that!

Download-only games.
I don't actually hate the downloadable games in question - no, not even close. I just bought Castle Crashers recently, and honestly, it's one of the best games of this gen (seriously, it's that good). The problem is I can't take the damn game with me, it's linked to the console (or gamertag). I want these games in a physical format, somehow!

Consoles imitating PC's (inheriting its problems).
naznatips said it best - required installs or patches, mixed with slowdowns hurts. Add to that the focus over online at the cost of local multiplayer, and games designed entirely around the assumption I have an HDTV (often unreadable text).

Multiplat games have a split online userbase.
A few friends with PS3's and Modern Warfare 2, the rest with 360's Modern Warfare 2. I'm forced to go with the 360, so I can't play the same game with the PS3 guys. I really hate this shit.

Higher pricetag on games.
I won't be falling for this one. Lower the price on games, or I'll wait until they drop in price, or even buy and sell them used. $60 for most HD titles, or $50 for a short single player game isn't going to fly - I don't care how much it cost the devs make the game, all that matters to me is the value (fun / entertainment) I get out of it. On that note, I don't want a PS3 for its Blu-ray player, I simply want the console for its games - don't expect me to pay $500 for a videogame console.

Removal of desirable features in the name of revenue.
This problem is not unlike the DLC issue. Take the PC version of MW2 - they removed dedicated servers, which is not only terrible for latency reasons, but makes little sense unless they want to charge us for more bullshit DLC (like maps that'd normally be free). Blizzard is going to remove LAN from Starcraft 2 (to fight "piracy"?), quite a difference from the Blizzard of old that let us install multiple Spawn copies (multiplayer-only) with a single disc.

I think most of the awful things this gen has brought us is linked to the rising development costs. Instead of trying to bring in more customers (like Nintendo has been doing), the videogame companies are trying to milk the current costumers, us, for all we're worth. I'm boycotting some of the games in question out of principle, these practices are unacceptable.

The idea that 'Better graphics = Higher Quality'. This idea was also around last gen, but people hid it away in the closet, because if they brought it out too much, then the PS2 would be blown away by the XBOX, GC and PC. Now that we have the holy HD consoles!!!!....its as if all inhibitions are gone and not only are people obsessed with graphics, they've even gone so far as using graphics as their ultimate measuring stick for the only reason to get a game.

The other thing I think that has been the ultimate downfall of this gen is the complete disregard for any tact from Reviewers for well...reviewing games. Last gen, they at least tried to look like they were being even to all the systems. But now, they just aren't even trying. Everything is just all about the praises of every new graphically powerful and popular game that comes out. From Halo 3 to Grand Theft Auto IV, if people show any interest in it, reviewers will talk it up to high heaven, regardless of the actual content of the game. They might as well give out stickers that say 'Approved for fun by IGN!'

FInally, this is just a personal thing, but people who think the only good games are on the HD consoles.

The neo geo finally dying after 14 years of support
and king of fighters no longer being yearly
very few games I've actually enjoyed compared to previous generations

fortunately Contra 4 largely offsets any cons
plus a new genesis game by the end of the generation will be quite nice

DLC

My top 3

1. The Wii
2. $60 games
3. Expensive accesories

Day 1 DLCs
Release now, patch later.
Year long exclusivity
this is exclusive...lol only joking
this is multi...lol only joking
This game is coming out on the 360...and...the 360...>.>...

Fanboyism.
I mean, there just systems meant to entertain us right? Its gotten so bad this Gen, that three of my friends quiet talking to me when I bought the Wii

Achievement Whores

You should play games because they're fun, not to boost some hypothetical score