is that they are traceable. Someone posted a site that traced all posts associated with you. It's been about 2 years ago, and I looked and sure enough a search on me yielded my posts here, which contained very personal information that I only wanted to share with others in the same situation. I stopped logging in and changed my username.
While I don't log-in, I do always post with my signature to identify myself. Nothing to hide here because I truly want everyone to be successful.
That's my $0.02.