Well, at Full Tilt, they play under their real names and you can see what rooms/tourneys they are currently in as they are highlighted in red. On the whole, they are also very good about answering questions from players and observers. Honestly, some of them seem to have the patience of saints...lol! Howard Lederer is particularly interested in sharing his poker knowledge with others. For example, when he plays, he will show every hand as opposed to mucking.
Edited because I somehow combined 2 Full Tilt pros and wound up with the name "Phil Lederer"...lol