Uncaught ReferenceError: _wpMediaViewsL10n is not defined at
This error appears from two different plugins of mine (enqueuing the same script, but from different places), on exactly the pages where those scripts are enqueued. I don't believe this error was present in 3.5 Beta 2, but can't be sure (no issues in 3.4.2 or beta 1). The script uploads images through the (old) media uploader/media library and inserts the urls into text inputs in the settings.
This probably has something to do with the new media features, and localization (l10n). It would be nice if plugins could use the new uploader for users to upload/insert media within plugin settings pages, but I'm guessing this either hasn't been implemented or hasn't been documented yet.