Based on their whim, your privacy can be completely invaded, and you can be thrown in jail. This happens ALL the time.
What is the NSA going to do? Bring you ("meddlesome kids") into court based non-admissable evidence from PRISM? Never heard of it happening once. Please cite a case if you disagree.
And bothersome people working way outside the law like Deepthroat, LulzSec, etc. already do take enormous steps to preserve their anonymity in communications. NSA changes nothing for me.