XBOX 360 Wireless Adapter (New)
The difference? The new dongle is compatible with the 802.11n wi-fi standard that is able to receive data at an eye-watering 300Mbps. This compares to the theoretical 54Mpbs upper-limit of the 802.11g compatible adapter currently available.
Also the range is multiplied so if you couldn't get a connection through the old adapter, this should definately work!