I don't have one....yet....but i do use a mouse that doesnt do it with my macbook pro. When i wanna go into exposé i do then 4-finger swipe. If you're working with a desktop, then the best ideas are either using the key for them on the keyboard, or you can use hot corners which can be found in the system preferences menu.
Thread on this earlier today using software called MiddleClick. Users have been reporting mixed responses but all in all it seems like a decent short term solution. I'm expecting Apple to issue some extra functions over time. Swipe, scroll and left/right clicking seems to be an awful waste of a touch sensitive device.
Before you say the site says it's for MacBooks etc. comment 72 states;
"I just tested, and this application WORKS with Magic Mouse!
Only downside is that you have to tap with three fingers, and not click, which seems a little getting used to.
Maybe something to look in to.
Anyways thanks a lot for your work!"