Skeptics are calling it Halo 2.5. But the Halo faithful? They're saying it's more fun than licking peanut butter off Sienna Miller's stomach. Truthfully, it lies somewhere between the two. Rack up frags in one of the beta's three new arenas—Valhalla, Snowbound, or High Ground. We're especially fond of the all-new Laser. Charge it up, then watch your enemies soil themselves as they dive for cover. The new spike grenades stick to walls/ceilings and, unlike the old grenades, they don't glow, making them tough to spot. There's nothing finer than hiding in the dark and watching an unsuspecting opponent wander near your 'nade and BOOOOOOM! Also new: Replays of your kill sprees can now be saved to your hard drive, so you can show your friends how you made quick work of RHODE_ISLAND_DAD99 that one time.