That's interesting, because it raises a few rarely-mentioned issues.
However, I wonder how applicable this is in the specific case of Honeycomb tablets. One would understand that 3rd parties creating SDKs out of the AOSP have "value-added" software (i.e. mostly stuff they pulled off the web and put in their SDK -- which is where the GPLv2 software you mention likely comes from, Busybox et al. presumably.) In the case of Honeycomb, though, which apparently Google has only given source access to a handle of pre-vetted companies, such 3rd party SDKs would likely not exist (right?). And, therefore, the actual Honeycomb shipped by said manufacturers should be snow white, so to speak.
And in the other cases, those of GPLv2-"contaminated" SDKs, this is likely no different from what embedded Linux vendors have been doing for over a decade now (i.e. a mix of packages from all different directions which still require the company shipping the product to make sure it actually understands what it's really shipping.) IOW, copyright holders still need to be on the lookout for potentially infringing parties. Which is no different from the way it was before Android ...
Any complementary info you could provide here would be great.