ive got a 600m with the 1.3 pentium m.
with laptops there are 3 kinda of intel processors currently being used as far as i know
Celeron / Pentium 4 desktop Model - Full blown desktop processor - sucks down battery life like you wouldnt beleive
Mobile Celeron / Pentium 4 -m - Mobile versions of the desktop processors, better battery life but basiclly the same thing
Pentium M (aka centrino, aka banias) - Newest line of intel chips for laptops, they have redone the artecheture (sp?) of the chip and it is better than ever. The PM runs on a 1mb l2 cache, i do not know the fsb off hand sorry. This is also a low voltage chip.
with the 600m expect around 4 hours of battery life depending on usage. Other centrino based notebooks have better battery life 5-6 hours or so.