Sony showed off a work-in-progress version of Gran Turismo 5 Prologue for the PlayStation 3. The near-final version of the game didn't differ much from the preview version we recently saw, but the press event gave Sony reps a chance to reveal some updates to the game. In particular, they explained the differences between the game that will ship to stores on a Blu-ray disc and the version that will show up on the PlayStation Network store.

For those who haven't followed it, GT5 Prologue is a meaty tidbit that Polyphony Digital is dropping for fans of the Gran Turismo series to tide them over until Gran Turismo 5 hits. The game has a respectable selection of gameplay modes, including online multiplayer, and a selection of cars for fans to hone their skills on in anticipation of GT5.

As in Japan, the game will come in two flavors: one you can download from the PlayStation Network and one you can pick up in a store on Blu-ray. The key difference is a documentary-style movie that offers a history of the series and follows the team as they go about their business working on the game. The behind-the-scenes flick will be exclusive to the Blu-ray version of the game, which will feature the same content as the PSN game without taking up the hard-drive space. In addition, GT5 Prologue will contain content not seen in the Japanese release, which hit late last year. Fans can look forward to 70 cars, exclusive music tracks, six racing tracks, 16-player online support, GT-TV mode content updates, and two-player split-screen play.

With the game so close to release, all we've got to say is check out the media we've taken for the game and drool. The wait won't be too much longer. Keep an eye out for our full review of GT5 Prologue soon.

  Normally a sample of an upcoming game is released as a free demo, or perhaps dangled as a promotional incentive for people who preorder the title. This week's release schedule sees an exception, as Sony will start selling Gran Turismo 5 Prologue for the PlayStation 3 at retailers and through its own downloadable game service for $39.99.

However, Gran Turismo 5 Prologue is much more than a simple demo. The game includes more than 70 vehicles and six different tracks (with some alternate layouts thrown in for good measure). On top of that, it marks the first time the series has gone online, with multiplayer races for up to 16 players.

While this Gran Turismo side project is the first to be sold in the US, Japanese gamers have been offered similar titles before. In addition to Gran Turismo 4 Prologue, Sony released a handful of stripped-down Gran Turismo Concept games, featuring as yet undeveloped cars featured in international auto shows.

Beyond that, it's a light week for console releases. Only the Wii has other retail releases scheduled, as Nintendo's system is set to receive ports of the PlayStation 2 hit Okami and the PC offering Dream Pinball 3D, as well as Summer Sports: Paradise Island.

PC gamers have a little more to look forward to, starting with Europa Universalis: Rome, the latest installment in the long-running strategy franchise. This week also sees the PC receiving a port of the Xbox 360 and PS3 shooter Turok, as well as a new Sherlock Holmes title and another Sims 2 accessory pack.

Gran Turismo 5 Prologue might be the highest-profile downloadable launch of the week, but as usual, the Wii and Xbox 360 are both adding to their online catalogs. The frantic Sega Genesis arcade shooter Mega Turrican can be added to the Virtual Console for 800 Wii points ($8), while Sega Master System shooter Fantasy Zone is available for 500 Wii points ($5).

Over on the Xbox Live Arcade, Pinball FX developer Zen Studios is set to launch its stand-alone Rocky and Bullwinkle minigame collection this Wednesday for 800 Microsoft points ($10). Atari also has another remake headed to the downloadable game service, as its original arcade tank game Battlezone will be released for 400 Microsoft points ($5). As with other Atari revamps, Battlezone will include original and enhanced versions of the game.

This week's new releases are listed below (list compiled from publisher and retailer information--actual dates may vary).

  Although Polyphony Digital's Gran Turismo 5 has been on the production line for some time, the game has proved to be more elusive that spotting an exotic supercar on the streets. However, racing fans may soon find temporary relief in the form of Gran Turismo 5 Prologue, a "lite," stripped-down addition to Sony's seminal racing series.