With the launch of the iPad 3 (iPad HD?) just days away, it stands to reason that there are a few prototypes floating around Apple’s headquarters in Cupertino, California. Maybe they’re using them for last minute testing. Maybe getting one early is one of the perks of working at Apple.

Whatever the reason, references to the iPad 3 are starting to show up in the server logs of websites. Ars Technica reported today that they had logged visits from 365 devices with a screen resolution of 2048×1536 – dimensions that are apparently pretty rare, but which match the iPad 3’s retina display exactly.

So far, no big surprise. As noted above, we shouldn’t be surprised to learn that there are iPad 3s already being used. The interesting part is what happened when Ars Technica started looking a little more closely at the iPads that had been visiting the site from Apple’s block of IPs in Cupertino. They found iPads running iOS 5.0.1, the current version of the software, as well as iOS 5.1, which is in beta and will likely launch next week with the iPad 3. Even more interestingly, though, they found some iPads running iOS 6. That means that the next major iteration is already far enough into development that they’re testing it on iPads.

Of course, the only thing that really tells us about iOS 6 is that it exists. Nevertheless it’s definitely interesting to see confirmation that Apple already has it in the works. While iOS 5.1 will likely release with the iPad, the major iOS updates usually launch with the new iPhone. There’s little real information yet on when Apple will launch their sixth iPhone (often called the iPhone 5). One recent rumor put the iPhone’s launch in September or October. Another report, only slightly less recent, suggested it would happen in June at WWDC. The September-October date would maintain the one-year gap between iPhone releases (the iPhone 4S launched last October). The June WWDC date would fit the pattern that Apple has followed with every other version of the iPhone.

At any rate, there are very few solid details about the iPhone 5 (6?), or about iOS 6. Expect the rumor mill to start ramping up in the next few months, once the dust from the iPad 3’s launch settles down. In the meantime, you can check out all our coverage of the iPhone 5 here, and our coverage of the iPad 3 here.