I have this question myself. Reading the respective overviews on B&H's web site, it appears that the V800 comes with 1 set of film holders and "Silverfast SE 8" software, while the V850 Pro comes with 2 sets of film holders, "Silverfast SE Plus 8" software, and in addition, "X-Rite i1 Scanner" software. Not 100% sure, but I believe the V850 comes with color targets as well. (Can anyone else vouch for that?)
Paul Watkins