Note how the fonttype of the "XBOX" text is the same as the one used at the end of the MTV commercial for the Xbox360 unveiling(see news) and also the same as on the Xbox360 design renders(see news) posted earlier this week.

UPDATE:
There seems to be small difference in the font that might indicate this logo is a fake. The leftside end of the middle horizontal line of the "B" is different on this logo. It's fully vertical here, unlike the "B" on the xbox design render and MTV ad.

The green 'circles' aren't new either for those who have been reading all the Xbox360 news lately. You might have seen this 'ring of light' before on the flash intro of the Xbox E3 Kickoff Celebration registration webpage and on the MTV TV-ad. The guys over at TeamXbox had an article about this 'ring of light' some time ago you may want to read too.