Thanks, everybody.
Ten posts before a signature line? That makes sense, and it explains why I couldn't even find a place on the settings page that even *talked* about it.
I'm very early in my search. I have a friend who loves his Nook, but I need to do my own research. I'm not in a hurry. My "deadline" is that I want to have an ereader before I go on a long trip, so I don't have to pack a briefcase full of books.

I think my next big trip will be this fall, so I have some time.
Thanks for all the welcomes!