I did not experience this on my original SP2, or the SP1. I have 4 co-workers in my department with a mix of sp1/2's, none of them experience this either and we all use various bluetooth mice, and we are network engineers so we would have noted pretty quickly if we were having issues, especially since we have to transfer large pcap files all the time.
The WIFI/BT module is the exact same as the previous SP2, hardware ID's match up exactly, this was just a minor CPU upgrade bump, nothing else.