We can look at past history for a possible answer.
Several new technologies have first come to the MacBook Pro (PowerBook) before the MacBook (iBook). These include Magsafe (2006), Lithium-polymer battery (2006), and 2-finger trackpad (2005). In all of these cases (IIRC), the MacBook/iBook got it in the next revision.
Now the larger multi-touch trackpad. It was first introduced in the MacBook Air (2008). The MacBook Pro got it in the February 2008 update, although the trackpad's size remained unchanged. The MacBook also got updated in February 2008, although it did not get the multi-touch trackpad. In October, all three notebooks were updated, and the MacBook and MacBook Pro got a new glass multi-touch trackpad along with a case redesign, while the MacBook Air remained the same. So in that case the multi-touch trackpad took longer than usual to migrate to the entire notebook line.
So to answer your question, I would think it's fairly probable, although it may take a while. If Apple indeed wants to add the new battery technology to the entire notebook line, then I would think that it would happen at or before the Rev. C MacBook (which is likely to happen late 2009 or early 2010 depending on Arrandale release).