[jspthrowaway2]

I've come across words in the OSPD that Words with Friends didn't take, as well as words not in the OSPD that it did take. A casual Google suggests that Words with Friends uses a modified version of a dictionary called ENABLE[1], so while it would be interesting data to see, the dictionary difference is a little troublesome for conclusions pertaining to Scrabble.

(You can, of course, play Scrabble with any dictionary but most serious folk I know use OSPD. I'd never even heard of ENABLE until Googling this question.)

[1]: http://blogmybrain.com/words-with-friends-cheat/words.txt