If you want to make an Android 3.0 tablet, you need need to meet specific requirements. Google posited a long time ago that when it jumped up to Android 3.0, it would act as a sort of reboot button for the operating system. That is, it would require much stricter hardware specifications to ensure there was cohesion among devices.
In order to battle the so-called "fragmentation" problem, Hanspree claims Google has a spec sheet required of anyone who makes an Android 3.0 tablet. That's why they have been so elusive so far. Only one - Motorola's Xoom - has been released. Anoehr one from Acer is due out later this month.
According to Hanspree, in order to get Honeycomb certification, the device must have a 1280x800 resolution display. There are other required specs, but those aren't detailed.
There is some debate about the required processing power, with some saying a dual-core processor is mandatory and others refuting that.
Nevertheless, it seems pretty likely there is some sort of specification requirement. It's just becoming surprisingly difficult to figure out what that is.