Marvel vs. Capcom 3 - There's a really good fighting engine here, but it's bogged down by X-factor. Including a mechanic in the game that lets just about any character insta-kill any other character with basic combos is just mind numbingly stupid. Beyond that, Phoenix is absurdly broken and the netcode is relatively poor. It's still a good game though - better than most of the stuff that came out this year. I just had really high expectations and the game came nowhere near them.
L.A. Noire - The story was enjoyable for the first half, but it nosedives after you get out of homicide. The detective work is too handholdy as well.
Earth Defense Force Insect Armageddon - Strip out all of the tactical challenge that makes EDF a great game and you're left with Bug Killer Musou. Boring.
Shadows of the Damned - A solid game, but I expected a more interesting story and cast of characters to come from Suda. Mikami must've done his best while overseeing the gameplay, but it's certainly nowhere near the same level as RE4 and especially Vanquish, so it's just kinda eh. Some levels are awful (horizontal shooter sections are shiiiiiiiiit), the game is short, and it has no replay value. Glad I rented it.
Otomedius Excellent - The easiest shooter ever just got even easier. Why.
On the other hand, here are some games that exceeded my expectations:
Bangai-O HD - I didn't like the DS game, so I was kinda wary going into this. But I'm glad to say that this game is MUCH better - it has a ton of extremely creative, well designed missions, it's challenging, and it's only $10. It's not as good as the DC version, but as an alternate take on the formula, I couldn't be happier with it.
Strania: The Stella Machina - I liked Grev's previous games, but I've never been a big fan. Strania is on another level though. Great music, great stage design with lots of variety, lots of weapons, nicely balanced difficulty, great soundtrack, lagless online co-op, and a good scoring system. I loved Bangai-O, but this is probably the best $10 you can spend on any DDL service. Oh, and you can pick up its sequel as a $5 DLC add-on. Ridiculous value.
Akai Katana Shin - I always thought I was going to like this game, but its poor performance in the arcades and the Shin mode demo made me temper my expectations quite a bit. But when I finally got the game and credit fed through Zetsu mode, I was completely blown away. Everything about the game is extremely well designed: the stages, the scoring system, the art, the graphics, the music, the enemies and bullet patterns, the pacing - literally, everything is A+ quality.
I guess I should've known better. Yagawa's games always seem to do poorly in the arcades even though all of them are so good. Maybe that's why they had him work on Daifukkatsu Black Label... so one of his games would finally make some money.