Everybody knows that when I fill out forms, under ethnicity I put 'Halo fanboy.' So yeah, I liked Halo: ODST. (For the spelling I would also accept OSDT, OTSD, and the M-for-mature title OSTD. Cue laugh track. Followed by Wilhelm scream.)
But why, 2K? Why did you like it? Draw close, my children.
Basically, this is the game we were ready for after Halo 2. Enough of that loopy green-and-purple palette. Enough growly Dirty Harry Master Chief dialogue. Can we all admit now that he was getting to be a drag? Healing up all the time, all the marine extras kissing his armored ass ... (I could never have enough slinky Cortana dialogue, but listen, I know I have a problem.)
ODST is different. It's noir. You've been dropped into New Mombasa at night. You've been out cold for six hours, and you're looking for the remnants of your scattered squad. There's atmospheric, vaguely bluesy soundtrack music. You're not the superhero Spartan anymore. You're an ODST (an Orbital Drop Shock Trooper) on his own, in an open-world environment, down on his luck, just trying to pick up clues and scrape up some semblance of a tactical win out of the jagged shards of a shattered mission. This is Starship Troopers rewritten by Dashiell Hammett.
They've tweaked the settings some to enhance the mood. You don't have a heads-up, top-down radar anymore, so when dudes come at you, you don't always know they're going to come at you, instead they come skulking in out of the darkness. And you're weaker now, too. You don't heal as fast. Sometimes you even have to clunk a grunt over the head a couple of times with your rifle butt before he falls over, staining the African dust with his creepy fluorescent blood.
And there's the pacing. Instead of speed-marching you through furlong after furlong of ringworld landscape, they sometimes slacken the pace and let you just be in the world. Sometimes you'll barely meet an enemy between checkpoints. You just walk. You listen to the ambient sound effects, and groove on the neon lights and broken-down cars. It's hella atmospheric.
(And listen, if you're a Firefly fan, it's a major major thing that Nathan Fillion, Alan Tudyk and Adam Baldwin are voicing characters. Though if you aren't a Firefly fan, you don't care.)
Basically, ODST is a big milestone. It proves that Bungie can use the same instrument to play in totally different key, thereby adding years to the life of the franchise. The major knock I've heard on ODST is the price-to-campaign-length ratio, which admittedly is not everything it could be. There's a lot of multiplayer goodness, but if you're single-player-focused, it's a slightly dicey purchase.
That's not a problem for me, though. See, I have a secret technique for squeezing delicious extra gameplay hours out of ODST: sucking at Halo. I recommend it. :0