p.s. I work for Code for America

Open Public: http://openpublicapp.com/ (Open source Drupal like whitehouse.gov) Achieve City http://www.achievecity.com/ (SaaS version of Open Public tailored for muni) City of DeLeon http://www.cityofdeleon.org/ (WordPress theme developed by Luke Fretwell of GovFresh) +100 to all the folks who said to be sure you have a long term service plan