From Reuters:

China commonly frees political prisoners before major state visits, but a human rights activist said on Friday changing attitudes meant there may be no releases ahead of U.S. President George W. Bush’s November trip.

The releases are seen as giving Beijing bargaining power before visits as a gesture of goodwill, but John Kamm, whose Dui Hua Foundation works to free Chinese political prisoners, said that thinking may be changing.

“There has been a change since the new leadership started,” he said, referring to Hu Jintao becoming president in 2003.