You (yes you) is a thousand times more powerful than the Bitcoin Foundation. Boycott any modification that makes Bitcoin no longer Bitcoin.
This post seems to strike at the heart of it. Community members, keep true to the manifesto! Don't accept modifications that subvert the public interest.
Do be a little bit cautious about this. Many people find many aspects of Libertarianism (and more generally, of various kinds of freedoms) to be somewhere between fringe and abhorrent. If/when Bitcoin becomes 'mainstream' it is very possible that the Bitcoin Foundation members ideas about blacklisting and such will have surprisingly broad support among the userbase.
My personal feeling is that there will be unintended consequences to a lot of the plans (e.g., control methods and fantastic userbase growth) which will eventually kill the solution even though the individual efforts will be successful and solving the narrow problems that they are engineered for.
At the end of the day, though, the cat is out of the bag. To kill distributed crypto-currencies means killing people's right and ability to interact. This would be challenging to do in a airtight and durable way, but it does not mean that it won't be attempted.