Get the MX 518 Gaming mouse has 2 well placed side buttons unlike the "improved G5 with extra fancy weights". Review here Matty
MX1000 is crap. ;P Sorry, but for gaming it is, I havnt get any of the new MX5XXs ones, but I had the MX500 and thought it was good, I currently use: Razer Diamoundback (charm) and RatzPad. They both are sweet. Im thinking of getting a new mouse too, I would go with either: Razer Copperhead, or Logitech G5 or Logitech G7. The new logitech mice, G5 and G7 look really nice, G5 is the same spec laser as in the copperhead, and the G7 is the same as G5 but just wireless. (Im currently thinking, of taking the copperhead and the G7 and mating them to breed the supermouse.)
Thats the name of my pad... RatpadzGS lol, the logo in the top righ hand corner has rubbed off - even though I don't ever use that spot on the pad Unless someone has been using it while im asleep