While the resolution isn't specifically mentioned, there is a designation: "MacBookPro10,2". MacRumors noted that the Retina and non-Retina models of the 15-inch MacBook Pro carry the designations of "MacBookPro10,1" and "MacBookPro9,1", respectively, leading it and Geekbench developer Primate Labs to believe the "10,2" is a Retina-based product. Similar specs to the existing MacBook Pro 13, along with another rumour mentioning an October release, means that if things work out, we'll likely see it in time for the Christmas season.
The first evidence turned up in July, which looked feasible; the new test, however, adds new data to the speculation machine, including the fact that it's running OS X 10.8.1, a version not yet released to developers.
While this could all be the cruel hoax of a trickster, it seems the stars are aligning for a more portable version of Apple's "resolutionary" product.