I fully understand that laptop computing is a different animal than desktop computing and things like heat, battery life, et al are vital to portables. With that being said, when's the last time a consumer product had a higher clock rating, let alone sheer performance edge, over the professional products? Obviously, I'm speaking of iMac G5 at 1.6GHz - 2.0GHz compared to PowerBook G4 at 1.5GHz.
Yes, again, I fully understand the concept of a portable, but I also understand how hard of a pill that is for the consumer to swallow. I know Macs and PCs are different animals and if you want X you get the Mac and such, but it makes it even harder to justify a $2000 - $3000 portable that would be outpaced by a $1300 iMac.
Here's my disclaimer. I have a PowerBook and I absolutely love it. Its all that I use. Then again, I wouldn't hesitate to pull the trigger on a PowerBook G5 in a heartbeat!
One other question. I know that PC manufacturers are moving away from using the P4 in laptops, at least that's what I've heard. How hot do the 3GHz P4's get? My boss has a laptop with a 3 (or higher) GHz P4 (desktop model) in it. True, its warm and gets horrible battery life, but I'd think with IBM's PowerTune technology, they'd be able to overcome many of these issues at 1.8GHz or so.