It looks like Snow Leopard might be coming a bit earlier than expected if slides from Apple's Director of Engineering of Unix Technologies, Jordan Hubbard are to be believed.  The presentation was given at LISA '08 last week in San Diego.  

Originally planned for "about a year" from WWDC 2008 (July), the change of schedule would be a significant bump in expections from people outside of Apple.  While Q1 extends to the end of March, this could also indicate that we'll see new Snow Leopard introductions at Macworld 2009 in January.  Perhaps even new devices using the new, optimized code?

The new release schedule would also mark a shortening of the development process which had been widening over the past few releases, though Snow Leopard may be considered a somewhat smaller update due to its lack of feature additions.

We should caution that this is only one person's presentation slide and could be factually incorrect, though he is certainly a person who would be in the know.

Via MacRumors