It's not worth it, at least it wasn't for me. Basically you get about 2000 in play money chips and you use those like real money to try building a bankroll. If everyone on the site used the play money as if it was real money then it might be a worthwhile training tool. But most of the players just play wrecklessly because it's play money. I watched one of the players who was in the top five play one of the NL ring games... He just kept going all-in preflop until he got lucky and tripled up.

There are a few good articles to read along with some decent audio files to download, but nothing you can't get out of some of the better poker books.