Version 2.0 apparently just "updates" the control panel's graphics and forces you to register your new MS Software or be nagged whenever editing your mouse prefs. Like KernelG, the registration page couldn't be found when I tried it (that's LAME, Microsoft) but at least it's stopped nagging me. There isn't a "What's New" Read Me file, so I don't know if anything else has changed. However, the software's functional, and I guess if I was the zany type who wanted my cursor to fly across the screen with the tiniest twitch of a finger, then I'd appreciate the built-in option to make the cursor faster than Apple's Mouse control panel. You can also use the control panel to change or tweak the function of the buttons.