As expected, AMD introduced the 785G IGP chipset today. The chipset is aimed at sub-$100 motherboards and supports AMD Socket AM3 processors. It's an evolution of the AMD 780G with integrated DirectX 10.1 Radeon HD 4200 graphics and several other updates.
PC Perspective published an indepth review over here, they say the 785G is a winner in the integrated graphics market.
AMD is still on a roll when it comes to integrated graphics. With NVIDIA concentrating on ION, and Intel still producing inferior integrated graphics, AMD really still stands at the top of the integrated hill. While it is debatable if that is actually a badge of merit to some, the engineering behind such a solution is still impressive. It cannot be denied that the integrated market is the largest single market in the PC world, and AMD has again staked its claim at having one of the best all around solutions. Now that AMD actually has processors that are competitive with Intel, it is a further advantage for AMD.
Another review can be read at The Tech Report, they conclude it's a subtle refinement of the 780G and one of the best choices if you're looking for integrated graphics.
So the 785G is a subtle refinement of the 780G, one that hasn't addressed some of the rough edges of the original. But then the 785G isn't exactly entering a market teeming with stiff competition. The only integrated graphics chipset that I can think of that's more capable than the 785G is Nvidia's GeForce 9300, but it's a bit of a power hog and nearly impossible to find on sub-$100 mobos. If you want to build a system with integrated graphics on the cheap, the 785G really is your best bet.