As of now, Congress.gov is a beta site and will remain a beta site until the shifting of all data sets from Thomas is complete. The full transition is expected at the end of 2014, and at this time Thomas will be permanently retired.
Congress.gov replaces Thomas with a system that includes platform mobility, comprehensive information retrieval and user-friendly presentation. It currently includes all data sets available on Thomas except nominations, treaties and communications. As mentioned above, all data sets will be included by the end of this year.
If you are interested in learning how to navigate the new platform, online training is available. Sign up here.