Looking for a powerful general use (including web development) laptop running Windows. Price points seem to be all over the place. Many less powerful machines are priced much higher than machines with better specs. How does one navigate this market? Are there any unpublished/under-publicized specs/bottlenecks you look for?

Understanding that hardware improves over time, is there an efficient ratio that can be used (or something similar, like Windows Experience Index?) which will indicate how powerful a system is? Thanks in advance!

P.S. Here is an example from a laptop released on September 17, 2010. Can anyone pick apart these specs? Is there missing information you would be looking for?

OS:             Win 7
Display:        16.4" LED backlit
Processor:      Intel Core i7-740QM, 6MB L3 Cache
RAM:            6GB DDR3 1333MHz (8GB max.)
Graphics:       NVIDIA GeForce GT 425M (1 GB of dedicated DDR3)
HDD:            500GB 7200RPM SATA Hard Drive
Removable Disc: Blue-ray with DVD±R/RW
Misc:           webcam/mic/speakers/bluetooth

(via Sony Vaio VPC-F137FX/B)