Like it says there, they're using Blockbuster.com now instead of True, but it should be switching back apparently. You sign up there, hit the link to True and sign up for a seven-day trial there, get a confirmation e-mail from the first site in three or four days that they know you signed up for True, then just cancel your True account and wait for them to e-mail you your 1600 points code in a week or two. I've got $180 worth of points through it so far. Doesn't take long to sign up and cancel.
edit: There were a couple of threads on GAF about it