Trying to nudge the format, I assume. Their regular discounts still hold, too; i.e., you buy two discs at 30% list, and get a third one free. On a side note, Warners is also reportedly going to start releasing catalogue titles at lower prices by the end of the year.
Anyway, the available titles can be found here. Some are good, some not so much. But hey, free disc when you buy two.