You will be able to continue posting pseudonymously, as some of you already do. (CK Dexter Haven!) You'll be able to post using a Google account, Open ID, or Name/URL. These choices are always visible on the comments dialog box.
I myself post on the Internet under my own name 98% of the time, for reasons of accountability and credibility. I use a pseudonym very rarely and only to protect the privacy of family members.
I use the "front page of the Times" test to determine how I feel about saying XY in public. If I'm not comfortable when I apply that test, maybe I should think twice about posting at all.