It looks as thought Apple is ready to begin seeding builds of OS X 10.8.1 out to developers. 10.8.1 will most likely include some bug fixes that were found in the recently-launched Mountain Lion, so we're not talking of big changes, just minor fixes.
OS X usually receives maintenance updates pretty quick after the initial builds land, which is due to the company wanting to push major bug fixes out to the public as quick as they can. The final version of OS X Mountain Lion was fixed two weeks ahead of the public launch, which means the Cupertino-based company was most likely working on 10.8.1 for quite a while now.
To compare this to other versions of OS X, 10.7.1 launched 27 days after the launch of OS X Lion, where OS X 10.6.1 launched 13 days after the launch of OS X Snow Leopard.