For IGP gaming, that would go AMD.
For gaming with add-on graphics, the advantage would be in Intel's favor in most game benchmarks.
If you run stuff in the background while gaming, they should end up roughly even.
The latest review shows in most scenarios that A10 and A8 Trinities beat the i3 2100 in Productivity, Media Encoding, Rendering and a lead in Gaming even @ 1080P. But yea the difference isn't day & night except for gaming.