For posting:
- invitations to games (you can also use the New Game menu)
- information about upcoming tournaments
- discussion of games (please limit this to completed games or discussion on how a game has arrived at a certain position ... speculation on who has an advantage or the benefits of potential moves is not permitted)
- links to interesting related sites (non-promotional)
I guess anything is possible, although Fischer always has been real careful about his privacy and I don't think he would be that overt in letting his real identity be known.
Those Internet Chess Games were always speculation as to whether Fischer played them or not. Something like an urban legend among chess players.