As PlateWire's popularity continues to grow, web sites of a similar nature are launching on a regular basis. After some discussion with other webmasters (including AboveAverageDriver.com's Chris) we came to the conclusion that this niche market would benefit from having one single clearinghouse to exchange messaging of license plates.
For instance, say Joe in California, witnesses Suzy's teenage daughter driving recklessly down the highway. Perhaps Joe does contact the authorities but they deem it low priority. So Joe goes home and send a "wire" to the plate, using AboveAverageDriver. Suzy on the other hand is registered on PlateWire to receive a notification if any of her plates are messaged. WIthout PlateXchange, Judy would have not received the message regarding her daughters reckless driving (unless she would have checked on AAD's website).
PlateXchange offers an Open Source system for web sites to communicate license plate packages amongst themselves.
So if you run a license plate based web site, or have a neat idea that you think would take off, but have avoided launching it, because others have something similar, now is your chance to participate in a growing network of niche web sites!