made some mods to FileUpload plugin ver 1.8.2 to work with 2.1 RC1 here. http://vanillaforums.org/discussion/26644/a-fix-to-make-fileupload-version-1-8-2-to-work-in-vanilla-2-1-backport
Very unlikely since 1) I'd basically have to take it back to beta for a change that big and 2) I really don't feel like cherry-picking those commits in when it'll happen naturally for 2.3 and 3) 2.3 is less far off on the horizon than you probably think.