Liftoff! Discovery is in orbit, and STS-114 is well and fully underway. The fuel sensor problem which had previously delayed the launch was not an issue this morning. Mission timeline, mission updates, and the Wikipedia entry.
Update: Fuel tank camera shows debris flying off the tank during separation, but it didn’t hit the orbiter. Future shuttle models of this type should have the spacecraft perched atop its initial propulsion stages rather than astride, a la Apollo, to avoid problems such as the impact which destroyed Columbia.
Update: Poor bird! :(