Regarding the P-series of intel procs, and their 10W less advertised power assumption.. unless you can get a good deal on them, in my opinion, they aren't worth the price. A T and P series clocked at the same speed give similar performance, except the P-series might run for an extra 10-20 min (haven't seen a test on this though, so I'm dubious about intel's claims), which isn't really all that important for my purposes. Lower power consumption doesn't necessarily mean the chip will have a lower temp either (dependin on revision). Although i think the P-series has slightly higher FSB support, I don't find that increase too helpful on a laptop anyway... T-series is always a lot cheaper too.
I know I didn't answer the thread question but I think that's been answered already.. just thought I'd give some more info.
Edit* If anybody wants to send me a P8700 (non-ES) sample I'd be glad to test power consumption with my T9400 (C0) rev against the P8700 in the same lappy!