Quicklook is broken in Lion [Turns out this is known bug #9536151]

I have a strange issue with Quicklook in Lion. This is on a clean install and happens with  more than one user. It also isn't fixed if I clean out the Quicklook cache in /var/folders

I have to push the spacebar twice to get Quicklook to work properly. 

The first time the usual Quicklook 'window' appears but it is blank:



Push the spacebar again and the image appears. If I restart the Finder the problem goes away briefly. It's driving me nuts.
This sounds like a bug; you can report it at bugreporter.apple.com with an Apple ID and password.

Can you reproduce the problem, then check for new error messages in /Applications/Utilities/Console.app? There's a small chance that this will indicate the source of the problem.