>Actually you have to go through Sylvan/Prometric to register, not the local testing center. And there might be an issue with the beta being available in all areas.

I called Sylvan and they didn't have any knowledge of either the 70-155 or 70-156 exam. They recommended I call MS and gave me an 800 number. Called MS and they said it isn't available in Beta yet and had no dates for when it would be in Beta. They suggested to keep an eye on the http://www.microsoft.com/mcp page for updated information.