http://commons.wikimedia.org/wiki/Special:Preferences#mw-prefsection-uploads
There's a new user preference "chunked uploads for files over 1 MB" for Upload Wizard.
The intent of this feature is to reliably transfer large files, mitigating connection reliability issues. This will enable us to raise the file size limit for all users.
Please help test this feature and report issues (performance, file corruption, errors, etc.). The carrot is that with this preference enabled, you can upload files <500 MB today (as opposed to <100 MB) :-)
The feature currently only works with Upload Wizard.
More information: http://commons.wikimedia.org/wiki/Commons:Chunked_uploads
Please report bugs on the talk page or against UploadWizard in Bugzilla: https://bugzilla.wikimedia.org/enter_bug.cgi?product=MediaWiki%20extensions&...