OT : perhaps wrong forum category, however....
long story short we wrote a webgl application round about the same time Sketchfab launched ... we decided to pull it life got it in the way however as it stands the code may give you some ideas and you guys are more than welcome to dig around our source ,granted your devs could proabably do this in there sleep...
same idea as sketchfab but we had a few additional extras .
1) ability to move and edit lights with a save function ." great if you want to control the lighting on the model "
2) subd on/off
3)dea format was supported so would could implement animation * we wrote a timeline
skip to the 1 minute mark
hopefully it gives some ideas , controlling the lighting personally from an artist perspective is great