Revise a couple sentences maybe?

We've got some special guests joining us from San Francisco for this hackathon. [Alan Williams](https://twitter.com/alanjosephwilli) and [Peter Welte](https://twitter.com/techieshark) from Code for America along with Ryan Branciforte from [Trailhead Labs](http://www.trailheadlabs.com/) will be joining us to work on open trail data projects. Alan has been working on the Public Land and Trail Specification (PLATS): an open, lightweight data specification for public land and trails. PLATS allows trail data to be easily shared between different local governments and agencies, and consumed on the web and mobile devices. There's already been input and activity on the specification from people and agencies all over the country. You can [read more about the specification and see it for yourself here](http://codeforamerica.org/specifications/trails/).