So I got tired of playing scrabble on POGO and Literati on yahoo....so Gf and I DL'ed the International Scrabble Club program. You play through their site with a little mini program, and its very nice.
Regular scrabble rules. regular scrabble dictionary. If you enjoy scrabble or the challenge of getting your butt handed to you by people you think you should be able to beat, check it out.
My wife has been playing on the Internet Scrabble Club for some time now. It's really the best place to just quickly load up and play a game. The ranking system is nice as well (earn points when you win, lose them if you lose, how much you gain / lose depends on your opponent's rank).