When creating a Crucible Review, uploading patches does not work using Google Chrome for Windows (version 3.0.195.33).
You can select a file, and click upload, and the page refreshes, but there's no patch present.
The exact same patch file uploads perfectly using FireFox 3 on the same client machine.
I've seen this across 4 or 5 reviews, both large and small, so it doesn't seem to be a problem with a particular patch file, path structure, etc.