First, to get things out of the way, I'm a bit of a Halo Whore. This is partially because of the gameplay, universe, and mythos; partially due to my being impressed with the cohesive marketing juggernaut behind the franchise; and partially due to my affinity for alliteration.
That aside, Halo 3: (I-should-have-been-called-Recon) ODST is a great game -- and an uneven one, all at the same time.
The game is genuinely fun, has some depth, is genuinely different than the previous Halo games, and has more polish as well.
Those strengths are also weaknesses, though, because there are expectations around the Halo franchise, and losing the über-bad-assery of Master Chief takes some getting used to, in addition to the gameplay feeling a bit gimped by removing the the Halo 3 "X-button specials" (especially since enemies still have them).
But I've admittedly got a bit of a skewed perspective, because you have to play a bit more cautiously as an ODST than as a spartan (health doesn't regenerate), and I recently started playing on a level above normal on games (so, "Heroic" on ODST), which made the gameplay and "easy-to-die" experience waaay more stark than it might otherwise have been.
And while the engine feels visually tweaked, and for the most part I really liked things like the HUD mechanics, Modern Warfare or the Frostbite Engine are kind of the technical bars for cutting-edge FPS games, so I'm really looking forward to Microsoft's and/or Bungie's making a break from their current tech to do something technically even more exciting.
Going back to the positive aspects of gameplay, there are some intense, almost amazing moments where you have to retrench in intense firefights that genuinely made me feel good when I finally busted loose and wiped the floor with wave after wave of Covenant. My criticism is I wish the checkpoints were more deterministic, because while playing the game on "normal" mode would make replaying inconvenient, replaying on "Heroic" or "Legendary" is a non-trivial time-suck.
And while I said I mostly like the HUD mechanic in the game, it is a bit confusing, and I can't tell whether the mechanic is slightly different for each ODST member, or if it varied based on environment, or what the issue was, but there were times when it felt like both the standard and enhanced HUDs were versions of unusable in the heat of battle. Which sucked a bit.
Oh, and game designers (all of you), please stop with sucky-ass escort missions. I get irritated enough at bone-stupid AI either running too far ahead or falling too far behind, but when I'm doing a mission where Buck is my gunner, and it's not an AI, but a pathing issue that gets him stuck for 15 minutes in a box corner? Give me a break.
This a rambly, back-and-forth assessment ODST, but make no mistake, it's a really good title, and I'm glad Bungie tried something variant from their previous formulas, and included a lot of the mechanics from other titles (theater, file share, etc.).
Is it worth $60? No -- no title is. But wait until I try out the Firefight and online co-op modes before I decide whether it's any worse than other over-priced sixty-buck games. Oh, and no one should pay $60 for games, between promos, Amazon pricing, etc. -- I try not to spend more than $40-50 for 360 titles, and $30-40 for Wii titles.
And for Halo 3 fans who haven't bought all of the add-on maps, you do get 24 additional maps as part of buying the game -- the 21 previously released, and 3 all-new jobbies. Not bad.