In order to carve $700 off the price of the A900, Sony cut costs in four key areas: the A850's viewfinder isn't as nice; it's burst shooting isn't as fast; the finish is a little less...finished; and the remote is optional rather than included. According to Sony, that extra 2 percent of viewfinder coverage is really expensive to attain, and the fast mirror mechanism necessary to gain that 2 extra frames per second in burst shooting adds a lot of cost as well.
