I am on Windows XP service pack 3.
Oddly I can't get it to give a really high tempo figure now, that I was getting before, but it does appear to be twice what it should be. I have just opened the program, gone straight to edit a song, then hit record and tapped out 4 bars of the song I'm listening too.
For me this could be quite a useful feature - although I have other means of working out the tempo, such as tapping in the various bits of music software I use.