They offer Google Transit Feed Data, and REST+JSON and XML interfaces for Los Angeles area agencies, stop location data, and schedule information. The site also has GIS shapefiles available for download.
Beyond making data available the site also provides some support resources to help developers do something with it. There is a terminology guide. The site also is a platform for 3rd party developers and LA Metro developers to interact. Most pages have a “comment” option for logged in users, and there is a developer blog.
“Beta” is a uncomfortable concept for some transit agencies; the idea of releasing something that is new and maybe even unfinished is an unfamiliar approach. But Metro appears to have recognized the benefit of the public beta approach — real-world use testing and feedback. By all appearances, this beta site is set up to anticipate and work with change. That makes sense because transit evolves and technology moves quickly. I’m looking forward to seeing the progress.