Since we won't get modifiers supported until depsgraph is fully implemented, this would allow people to use Blender internal in the viewport to see the status of an object.
The idea was to move to core profile ASAP without loosing ability to see modifiers in BI for until we've got proper depsgraph system in place.
This is a temp solution, which is not optimized or anything and only aimed to show some solid mode.
It'll be removed as soon as proper DEG system is in place.
Think we can close this report now, since all the work is finished here.