Or the massively overlooked, and massive, music & sound recording/mixing areas. These advances make native processing in Logic/Pro Tools/etc an ever-more exciting thing. If the i5 comes up with the goods, I may be able to leave tower computing behind for laptops.
True...and in fact I work in the sound arena...but not with ProTools...I use Acid and SoundForge among others.
Buttttttt...I do this all on a desktop. And, the soundcard is what really provides the bulk of the power of what your sound software can and cannot do. The software checks to see what the soundcard is capable of doing...if the card doesn't support A,B, and C, the software simply doesn't give you that functionality.
Assuming your non-integrated soundcard works just fine with your software, CPUs do become important if you are going to push your software to its limits.
But again, we're talking consumer vs. professional here. Any pro is going to spend tens of thousands of dollars on heavy equipment and redundancy. Consumers or music producers working at home with less budget will do just fine using a quad-core chip today as a dual-core from 3 years ago as a single core from 8 years ago. Seriously. Unless they are trying to run 32 or more tracks simultaneously with all sorts of software-created effects, etc...which doesn't sound like the average consumer or even averge home-based music consumer.

There's an exception to every rule.

And yes, if we are talking about people using their laptop to do such music production, sure, faster chips are always appreciated on laptops because laptops typically are a few years behind in speed/performance than their desktop counterparts...regardless of how much money you have. Now, anyone who uses a laptop with a 15" or even 17" screen to do music production (other than for a fun hobby 1-2 hours a week) better have a darn good reason why they bought a laptop instead of a desktop (with more power, larger screens, and cheaper cost).
I usually create music pieces with 10-15 tracks depending on what I am doing...all tracks are WAV so compression (Mp3) is already out of the picture. My 3 year old quad core 2.3GHz chip with 3GB memory and a few hundred gig SATA 7200RPM drive works fine and has for 3 years. Before that it was the same amount of RAM on the same OS with the same spec drive (probably smaller storage) with a single-core chip which also was 3 years old. So for 6+ years I've seen, in my daily and above-aver usage of this machine, 0 problems or reasons to upgrade. The only reason I did upgrade was because the machines were so cheap and came with new warranties and a few extra bells (faster dvd drive, more cabinet space for SATA drives,).
On average I buy a new pc every 3-4 years...mainly because the new ones come with extra bells and whistles that the old ones did not. Never have I needed to buy a new Mac or PC because the machine died. My mom's ancient 8+ year old WinXP pc with a Celeron chip still runs just fine these days with Youtube, iTunes, web surfing, Office, etc. But her usage is quite light. I've burned and ripped cds without a hitch as well as ran some other apps she doesn't run...that's why I state that on average for most consumers, chip speed over the last 10 years really hasn't been that much of reason to buy a new computer.
-Eric