The main diff. seems to be the drivetrain.
Shifters Shimano Deore LX, 9 speed
Front Derailleur Shimano Deore LX
Rear Derailleur Shimano Deore XT "Shadow"
Crank Shimano Deore LX 48/36/26 w/chainguard
Cassette SRAM PG970 11-32, 9 speed
Pedals Shimano 324, single sided clipless
Brakeset Shimano M431 w/Shimano LX levers
Shifters Shimano Deore, 9 speed
Front Derailleur Shimano Deore
Rear Derailleur Shimano Deore
Crank Shimano M443 Octalink 48/36/26
Cassette SRAM PG950 11-32, 9 speed
Pedals Alloy w/Kraton inserts
Brakeset Shimano M421 w/Tektro levers, Kraton inserts, bell
In everyday life for a casual rider that hopes once he gets in better shape to do some nice rides (I am thinking maybe 40-100 miles on a good day), but still not striking out for a New York to Calif. run is there much that can justify a +$350.00 difference in these two bikes.
I test road a 7500 today, and liked it---LBS doesn't have a 7700 to ride so I am stuck in that regard.