Starting with the message that it is “For Internal Use Only,” an information-packed new trailer for Forza Motorsport 4 has found its way to the web. Full of news about the cars, tracks, visual effects, and Kinect support coming to Microsoft’s flagship racer, fans aren’t going to want to miss this.

Forza 4 was first revealed at the 2010 Spike VGAs, where it was one of the very few genuine surprises of the evening. Though the trailer that debuted that night gave some indication of what to expect from Turn 10 Studios’ next stab at automotive supremacy, the new trailer really delivers the goods.

The video is only available in 360P currently, and the possibility that Microsoft may have it pulled certainly exists, so catch it while you can. Check out the newest in-game footage from Forza Motorsport 4 below.

So much news, where to begin? Though it may not be the most appealing aspect to die-hard sim-racing enthusiasts, the degree of Kinect integration in Forza 4 is significant. At one point, Turn 10 had suggested that some sort of “walk around the car” mode would be patched into Forza 3. That has clearly been vastly expanded for implementation in Forza 4, though I can’t help but wonder how popular that feature will ultimately prove to be. It seems like something players are likely to mess around with a few times and then never return to.

Meanwhile, the jury is out on the head tracking feature that allows players to look into turns. If it works well, it could be revolutionary. But if it doesn’t work well – if it is overly sensitive, or not sensitive enough, or “twitchy” – it could cause more problems than it solves.

Now, using Kinect to dive in the game – that’s a whole other matter. Showing a father and son racing against each other sitting on the couch seems both a deliberate display of the feature’s intended audience and perhaps a revealing portrait of that control method’s limitations.

Having played Kinect Joy Ride and Sonic Free Riders, I am well aware of the Kinect’s shortcomings as a driving game interface. The lag inherent to the device simply doesn’t marry well to faced-paced games that require fine degrees of control. For that matter, how will acceleration and breaking be handled in Kinect mode? Still, as a sort of “bonus” on top of a clearly feature-rich game, the Kinect integration does seem kind of neat.

And feature-rich is exactly what Forza 4 appears to be. Hundreds of cars from over 80 manufacturers, hundreds of tracks spanning the globe, online car clubs, 16 player races – it’s quite a list.

The trailer states that Forza 4 aims to be “the best looking game of 2011,” and that will be no small feat. As good as it has always looked, to my eyes Forza has long seemed to have just a bit of the “Blue, Blue Sky” aesthetic of classic Sega arcade racers, with really clean tracks and highly saturated primary colors. Forza 4 promises “image based lighting” and “a photo-realistic look,” and indeed the colors in the trailer do look a bit more muted than in previous editions.

Personally, I hope the finished game remains as vibrant-looking as Forza 3. That the designers promise “new Hollywood-style visual and audio effects” makes clear that they are aiming for a dynamic visual approach – and also that they may have spent a little time playing EA’s Shift games.

Aiming to mix challenge and accessibility is no small feat. So far as we know, Forza 4 has the racing genre largely to itself this Fall. In trying to make a game that appeals to everyone, will Turn 10 deliver a game that satisfies no one? Or is Forza 4 going to be the sim-racer that finally reaches a larger audience than the king of the genre, Gran Turismo?

Update: Just as we suspected, Microsoft has pulled the video from YouTube. Addressing the matter, a Microsoft spokesperson issued the following statement:

Specifically what features and functionality may not have been accurately reflected in the promo spot is anyone’s guess, but Kinect integration seems the most likely suspect.

“The video in question was not intended for public distribution and may not accurately reflect features and functionality that ship in Forza Motorsport 4. We will have more to share on Forza Motorsport 4 in the near future.”

Though the meager video quality of the trailer  suggests that it may indeed have been released under questionable circumstances – the footage was clearly marked as “For Internal Use Only,” after all – the no-longer available Forza Motorsport 4 trailer was extraordinarily polished and well produced. Could it be that Microsoft and Turn 10 were clandestinely attempting to gauge reactions to the proposed feature set? When the next batch of Forza 4 news makes the rounds, we should have our answer.

Forza Motorsport 4 will release in 2011 for the Xbox 360.

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