Direct2drive, the hugely successful digital distribution service and competitor to Steam, is moving home for good. The service will merge into GameFly in January, taking all of its already existing accounts with it. All you'll need to do is change your password when you sign in for the first time and everything will be set up.
With a brand new client available and a new website on which to buy, pre-order and download games, this is a decision they've obviously took quite seriously; the only real shame is that there are a few caveats – you're older, less popular games might not make the jump across and your Prima strategy guides (and other non-game files) won't be available from GameFly, so you have less than a month to get a hold of everything not making the jump.
I have no real opinion on this, I've never used either service. I know that people out there were disappointed when GameFly bought Direct2Drive earlier in the year but I'm not sure it has been an on-going complaint. So I guess at this point, the best bet is to play the wait and see game.