Anyone else got one of these yet? Picked one up today to replace an aging MS optical (CompUSA, $79). I really like it. Feels very sharp. The new tracking engine uses a IR Laser instead of a LED for tracking, so tracking resolution is much finer. Logitech claims 20x optical performance. And it works on some optical-unfriendly surfaces. I tested mine on glass (works) and clear plastic (didn't work). Guess the plastic is just too smooth a surface. Its wireless, like the MX 700. The battery has been upped to a Lithium ion unit, and a LED charge indicator on the mouse. Most important, none of the extra buttons (it has a lot: scroll wheel, a rocker switch around the scroll, another rocker on the thumb side, and a button inside that rocker) get hit by accident when using it. Plenty of room around the buttons. So anyone else pick up one of these uber-mice yet?