It's curious that even though you think "Google is even required by law to enforce its copyright" Microsoft somehow manages to let it go in regards to developers for the WinMo platform. Maybe when you're big enough, you can just ignore the things you're "required by law" to do? Or maybe they realise that when you have a completely rubbish mobile operating system (Android, WinMo) encouraging development for it is more important than getting bent out of shape about what you have the right to do?
Either way, regardless of what Google *can* do, what they *have* done is incomprehensibly shortsighted. Perhaps the new telcos signing on to Android (the poor bastards) have forced Google's hand, but it's still intensely bad PR. It's like me going after a kid's lemonade stand because they don't have a license or haven't been inspected by the FDA or whatever. Regardless of how high and mighty I can be about your authority to do so, or how legal it is, it has no potential to make me look like anything other than a spanner and every potential to backfire hideously.
Of course, given the geek attention span of "until the next shiny object" I predict the outrage in the Android community to taper off within a week, which is what Google wants and expects. I do think that come time to re-enlist (my contract with TMo is up in January) there will be more than a few people dropping the platform (what with it being complete rubbish and no credible alternative now existing)