There are several of us that have been having similar problems with bluetooth mice on the mac for at least a year now. If you look under jumpy mouse or erratic mouse or selectively slow in the bluetooth forums you will see hundreds of us with similar problems.
We have discovered that bluetooth mice seem to be selectively slow when downloading a large file or copying a large file or if a program is demanding significant resources. This slowness in slow motion looks like a jumpy mouse - no response and then an overly large response.
I have posted a video of the problem on Youtube. You can read additional comments there.
http://www.youtube.com/watch?v=OBzisliiVpg
My advice is to contact Apple Care and notify them of the problem. Don't be surprised if they claim not to know about it. This seems to be a common response. In addition, notify Apple by going to Apple.com/feedback and sending them an email. Eventually, Apple will figure out the source of this problem.
Finally, the problems don't exist in Bootcamp - Bluetooth mice are perfectly smooth in Windows. The problem exists in OSX - Amazing!