Since I’m continually running the latest betas or versions of software and add-ins – every once in a while my system will get in a wonky state.  I was having the issue where PowerPivot and PowerView weren’t showing up in my Excel 2013 ribbon and noticed a couple of others were having the same issue – If you’ve run into this problem, take a look at the Excel Support Team blog post - Excel 2013 PowerPivot or PowerView add-ins are not available and then follow the directions on updating your registry and you’ll be back in PowerBI heaven using PowerPivot and PowerView.

Cross Posted from Dan Fay's Blog (http://blogs.msdn.com/dan_fay)