I emailed them to find out when they were comming out with the driver... they told me that they were still working on it... that was like 3 months ago. (They responed to my e-mail in less than 24 hours!) I saw that the beta came out... I havent tried it ... I might just wait for the full thing.
I have downloaded, but not installed, the beta drivers. I have found that the mouse functions as I need it to without drivers. I have the Macally optical mouse (three button), with the wheel functioning as well as both buttons.
I would be interested to hear what the drivers do differently, and will probably wait for the non-beta version to be released.