Yes, now that the mission is over, the spacecraft is doomed to remain in its orbit as a piece of space junk. As far as I know, there are no plans to retrieve the spacecraft, or to use it in any other missions.

The important assess now is the information contained in the data that was captured during the mission. The data must be thoroughly analyzed. It will take another 18 months, or so, before the Gravity Probe B findings are officially released, which would make a offical relase date of the findings around April 2007. Do you think Einstein's theory of frame dragging will be confirmed?

Regards,

LelandJ