updating from windows8 to 8.1 on my imac, failed and restored the original win8. any ideas? or is it not possible yet?

Hi there. I have the 64bit windows 8 running via bootcamp on my 2011 imac. I am not really a fan of it, but need it for a few apps. I thought I would update it to win 8.1 as a free 'upgrade", so after downloading over 3 gig of update, away it went installing...... the machine rebooted a couple of times, all seemed to be going ok, then a black screen, no activity, and after about 30mins, i thought clearly something's not right? I had to reset the machine, and windows is now restoring to the previous version. I can only assume it is a driver issue and I can find no mention anywhere on the apple site about win 8.1? Would I be right in assuming there maybe an update to bootcamp in the near future?

thanks, regards Kim