all in one= most accessories on board i.e: sound, video, lan, modem etc. like sniper said. i haven't really seen any name brand all in-one boards. it's mostly cheap boards that are all-in-one
nVidia just released a new chipset for intergrated graphics that sounds great (for intergrated). It is the GeForce 6100.
Check out dailyrotation.com for linkss to the announcement. Digitimes is carrying a bit on a Biostar socket 939 barebones based on the new chipset that will be out around October.
The 6100 will support DirectX 9 and Shader Model 3.0.