I'm guessing they let it lapse but managed to get it back from whoever snatched it up. But that's just a guess.
According to WHOIS, it was just updated today (May 9) and expires next May 9. Current contact is someone with a rpgshop.com email, so it looks like the original people own it now. However, is also says that it was originally purchased May 3, 2000. Since these go on yearly cycles, I'm guessing it lapsed May 3rd, someone else snatched it up, and then RPGNow got it back and updated it today. So it would take a bit to propagate back out if it is getting set back. But DNS propagation is a pain in the butt, drawn out process so it'll be sporadic and based on your local ISP for the next couple days I imagine.