For Christmas I got a new Canon 7D camera to replace my old trusty 30D.  The 7D features a higher resolution sensor and a built-in automatic sensor cleaner.  Both of these features as well as some better environment seals made me get the 7D.  After travelling all over the world with my 30D, the biggest problem was dust on the sensor and in the reflex lens.  The 7D minimizes this with the sensor cleaner and the seals.  I’m looking forward to having a more dust free view.  Time will tell.