One of the questions I asked the Infinity Ward team at E3 was what engine improvements were made in
Call of Duty Modern Warfare 2. One of the responses came back was texture streaming for better detail. It's hard to see how this improves the look of the game while you're watching the action but a
post on FourTwoZero.com shows off a comparison picture of what they mean. As you can see, the details on Soap MacTavish's head and clothing are a lot more detailed with the streaming technology on. Without it, it's a lot more muddled.