From what i can tell other then the WMPNetwork process when it is running my ram is pretty well under control... I tend to close down everything except what im using and i stay below 20-30% Ram usage from just Win 7 64Bit. This screen shot is taken while the WMPNetwork process is closed.
Also I found another temporary solution. The process WMPNetwork is actually a "service" and at the moment I have prevent the service from be able to load by disabling it. But this forces me to have to go into services whenever I want to stream video to my 360. While steaming video i aboviously expect my PC to perform badly. But even when its not steaming and the WMPNetwork is loaded it performs badly this is also with my 360 shutdown.