In case you didn't read the readme for UR2, UR2 for 2012 Revit products patches content files that are part of your installation. Some of you might not use the out of the box families, but if you use the templates, this is still important because some templates have been patched. Also, make sure you look at the note about updated shared content.
Here is the listed on content patched by UR2 (click the image to make it bigger):
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Please define Content Files "Patched" in what way are they different to those already installed
Posted by: www.google.com/accounts/o8/id?id=AItOawn5DXji3JQKDy7vobU4rkdYRVIguqWRSEU | September 29, 2011 at 03:04 PM