I downloaded the latest Logitech software. It was better, but still not close to the smooth, fast tracking of my current Logitech wireless (but it's going to die SOON...)
I'm going to take it back, and since I'll be down in Cincinnati next week, I'll go to Apple Store and take a look at the Mighty Mouse.
http://www.logitech.com/index.cfm/pr...CONTENTID=8066
^The mouse in question. I'm going to try it one more time in a little while, and if it still is bad, it's going back.
And nope, no fast user switching. Only one user on this Mac.