I'm sorry to hear you're having problems with the upgrade. If you can please provide us a URL for the exact installation you are updating, then we could take a close look at the issue for you. I am not sure which account is yours and what installation you are referring to, but if you can provide a little more information we can definitely troubleshoot the issue for you and give you a solution. The answer that John Paul was referring to comes from the WordPress forums here: WordPress.org support forums: Destination directory for file streaming does not exist" which then points to this article: Troubleshooting WP master list.
Please provide us more information and we'd be happy to help.