I love Logitech gear, their keyboards and mice (amongst other things) rock. Up until I recently changed to a Microsoft Natural Laser Mouse 6000, I had always used Logitech gear, including their S530 keyboard and mouse combo for the Mac.
Their latest offering looks very nice. The MX1100 cordless laser mouse has a total of ten programmable buttons, that include their Stealth Thumb Button. This one is strategically placed where your thumb would naturally fall, making it easy to switch between applications. Improved battery life is also claimed. Costing just under $80 in the USA with official UK pricing TBC, although I have found it for £50 on pre-order at some UK websites. Expect to see a video review on Geekanoids in due course.