I still play it occasionally. Actually I'm back to it with the latest expansion. It scratches my itch for questing/leveling style of play. I kinda like the PvP also, but haven't done it much with the latest expansion. I hear they changed it somewhat and don't really know what the general feelings are about the changes. I also started WoW back up, but after playing Rift I just can't really get into it. WoW is just scratching my nostalgic itch - nothing more to see there.
I seriously would like to try and do the raids, but they are so complex and I just don't have the skills to help out those who have been memorizing the mechanics to be of any use other than cannon fodder.