I've been dealing with browser-based large file uploads, which means dealing with lots of browser-specific issues.
Fortunately, things are getting better, especially for the webkit-based browsers. Firefox still has some issues, and I check https://bugzilla.mozilla.org/show_bug.cgi?id=678648 pretty regularly. Just today this bug, which was filed in 2003, changed from Status = NEW to Status = ASSIGNED.
To clarify, bug 678648 was logged in 2011 and is marked as a duplicate of bug 215450 (the one from 2003): "uploading files that are larger the 2GB fails" @ https://bugzilla.mozilla.org/show_bug.cgi?id=215450
That title is a bit misleading.. On some platforms you can already use Firefox to do >2GB uploads, but there is still a 4GB limit..
If anyone wants to help beta-test a HTML5 uploader that calls archive.org's S3-like endpoint under the hood (no IE or Opera support yet, though Opera 12 is now working..): http://archive.org/upload/
Fortunately, things are getting better, especially for the webkit-based browsers. Firefox still has some issues, and I check https://bugzilla.mozilla.org/show_bug.cgi?id=678648 pretty regularly. Just today this bug, which was filed in 2003, changed from Status = NEW to Status = ASSIGNED.
Today is a good day.