I don't use my real name on facebook either, and I know many other folks who do the same. Indeed, I might prefer to use my real name on NewsTilt but NOT facebook.

As with many of the login complaints, this is probably only an issue for a small minority of your target users.

Really? Interesting. I presume though that it's a name that you're invested in somehow, and that you wouldn't like to tarnish by leaving crapping comments?