The screen shots below might be a rare sneak peak of the new App Store. As to whether they’re fake or real, only time will tell and it’s up to you to decide. From what I can gather from the images, the look of the supposed App Store appears to be very similar to installer.app with notable features include the ability to browse Featured, Genres, Top 50, Search and Updates.

[Thanks for the tip Mike, Monsterandfriends]

[UPDATE - 6PM] TUAW reported the following that seems to support the images above:

Today, I downloaded the latest storeBag.xml from Apple's public iTunes server. What I found was this:

There appears to be a new service, labeled "p2-panda" that offers access to the same functionality that Cory reported on last night. Specifically, the panda calls include StoreFront listings, Genres, Top Fifty listings, and Updates. If nothing else, this independently confirms functionality seen from those screen shots.

At this time none of the calls appeared to function--whether from a Mac or from an iPhone--but I do not have access to the AppStore software itself, only to the protocols and web browsers. I'll try testing periodically in case the services pop back online.

Update: p2 likely refers to Purple 2, the iPhone code name. (Thanks Ryan)

Update 2: iPhone developer asap18 reports that the AppStore allows users to search for iTunes music as well as applications. This leads him to believe that AppStore extends the core iTMS functionality on the iPhone.