The JWST was actually planned back in the early 90's and annouced in that time frame too. In 1995 there was a big change in the budget for the project when it was sent to a 3rd party Northrop Gruuman to fabricate. One of the lead optical engineers, Dr Philip Stahl, actually just gave a talk on it at the UofA.
http://www.engineering.ualberta.ca/d...ID_event=10354
The JWST should be interesting in making or breaking alot of cosmology and and other physics theories, and probably even some religious beliefs.