Ever since the Xbox's launch, the system has managed to amass a library of games that has capably spanned most every available genre. Racing has, in particular, been one of its strong suits, with strong third-party support and stellar first-party offerings, such as the Rallisport and Project Gotham franchises. However, as fine as both arcade-style racing series are, there has been one gaping hole in the Xbox software library: a racing simulation. But that gap will be a thing of the past when Forza Motorsport hits the Xbox early next year. The unique first-party game has been cooking over at Microsoft's first-party development studio for the better part of two years, and it aims to offer a sim experience that has something for everyone. While it's a tall order to serve up something that will appeal to hardcore racing sim fans and more-casual players, Forza seems poised to do just that with its robust offline and online gameplay features.

Forza Motorsport should appease Xbox owners fiending for some racing sim action.

You'll find five modes to choose from in Forza: arcade, career, multiplayer, free run, and time trials. Arcade lets you hop onto any available track--with any available car--for a fun race against either the Xbox's artificial intelligence or a friend. Career is the meat of the game, and it will send you off to test your skills across 60 tracks. The mode differs a bit from the traditional career modes we've seen in other racing games because of its profile system. When you first start the game, you'll create a profile that you'll bind to one of three regions: North America, Asia, or Europe. This choice will affect both the cars you'll encounter in the game and their costs to you. For example, a player with a North American profile will have access to a broader array of American cars (that also sell at much more reasonable prices), whereas someone bound to Asia or Europe won't--and vice versa. The list of manufacturers in the game is extensive and reflects the development team's passion and/or obsession with the genre. You'll find 60 top manufacturers represented in the game, including Mazda, Nissan, Mercedes-Benz, Honda, Chevrolet, Ferrari, Porsche, BMW, and Dodge.

You'll earn cash to spend on upgrading your ride by winning races. Besides shopping for new sets of wheels, you can also choose to upgrade your car via the system's insanely detailed customization feature. You'll find roughly 40 ways to tweak your car under the hood. You'll be able to take your car to the garage to either alter or install alternative engines, suspension kits, bolt-on superchargers, brakes, rims, racing slicks, fine-tuned gear ratios, fuel-mapping, forced induction pressure, tire temperature and pressure, and ignition timing.

The graphics in the game are a stunning use of the Xbox hardware.

Although this may sound daunting, the system is broken down into three logical chunks: engine & power, appearance & aero, and chassis & drive train. Each chunk will have a number of upgrade types (specific to its subject) that you can tweak to your liking. While the interface we saw was still placeholder material, each option will likely have some form of dyno curve that will change dynamically as you highlight different tweaks, which lets you know how your car's performance will be affected. The customization runs deep and will even let you swap engines between cars in the same class. As a result, you can pop an Acura engine into a Honda Civic for some extra muscle. Besides the meat-and-potatoes tweaking you'll do to buff up your car's performance, you'll be able to make sure it looks as good as it runs by doing some work on its exterior as well. You'll be able to trick out sport compacts with real-world body kits, rims, spoilers, decals, side skirts, fender flares, and hood scoops, or you can add motorsport decals and team paint schemes to supercars, GT racers, and exotics.

Multiplayer should provide a compelling experience that's equal to the offline single-player game thanks to two simple words: Xbox Live. While offline split-screen play is well and good, Forza's online play should have a lot to offer. While Microsoft isn't revealing everything about the mode just yet, it's dropped some tantalizing hints. Besides the standard versus-play options for up to eight players, you'll also be able to join or create your own car clubs or trade cars, and you can check your standings across a whopping 1,700 leaderboards. Finally, the free run and time trial modes let you hone your skills and garner the best times on various tracks, respectively.