Top screen shot was from 10:06 AM this morning.
Bottom screen shot was from 10:51 this morning.
It looks like they are trying to keep the WotC releases from squeezing out the indie releases on the Hottest Items lists.
Same happened at RPGNow, but I didn't think of grabbing the screen shot until the moment had passed.
I don't blame OBS for doing this at all. The WotC stuff will sell no matter where it falls on a list (or fails to fall depending on how they work it) but placement on these lists can be the bread and butter of indie sales.
Falling of the list means slowing sales, and that hurts both the indies and OBS.
And just as I was about to hit send, the first list is back up - it looks like there is some major tweaking going on behind the scenes.
RPGNow's current list is WotC free. Let's see how long that lasts ;)