Quick Look taking FOREVER after upgrading to Lion

Hey everyone. I have a mid-2008 24" iMac running with 4GB of memory. I recently upgraded to Lion and almost everything seems to be working great. One thing that is not working, however is Quick Look which is really not working at all. Back on Leopard or Snow Leopard, I would open up a folder full of jpgs, hit the Quick Look button and a preview of the picture would pop right up. I could then even arrow through the folder with each picture showing right up.

On Lion, this is not the case. I open a folder or picture files now, hit the Quick Look button and the picture comes up after about 30 seconds. Now, when I arrow around, the title for the Quick Look window changes but the new pictures never come up. Is anyone else having this problem? This is very frustrating and I am not sure why this feature the older OSs worked fine a but not now. Any help would be GREATLY appreciated.