Hey there. I've added instant previews & file sizes (for recent versions of Chrome & Firefox) to UploadWizard.

It's on commons.prototype right now; would anyone like to try it and let me know how it's working for you?

http://commons.prototype.wikimedia.org/wiki/Special:UploadWizard

There aren't a lot of other bugs fixed at this moment -- rest assured they are on the agenda...