openxcom.org is the official OpenXcom website. We run it. It’s where you are, right now!
openxcom.com is the unofficial mod site. We have no control over it. We realize this must be very confusing, sorry!
Anyways, the mod site is currently suffering difficulties due to a huge surge of traffic from RockPaperShotgun (thanks for the article btw!), so you may have trouble reaching your favorite mods. But don’t fret! You can also check the mod forums, all the popular ones will likely have mirrors.