I can't think of any more expensive components that will be out of date more quickly than what you've picked. Penyrn will run on socket 775, Nehalem won't. Raptors are about the worst you can do in terms of price/performance. SLI is buggy and app dependent. About the only thing missing is DDR3.
By the end of the year your top dollar system will be obsolete. "Future-proof" is an oxymoron.
I suggest 1 raptor as the system/app drive and 1 large drive for data. This will much better protect your data from crashes.
I don't think you need a sound-card unless your very serious about sound or have some special need for that card. On-board sound cards are getting good these days.
Don't waste money on DDR3 yet.
Try the stock cooler before getting a high-end cooler, as others said, 45nm parts should run cooler than the 65nm C2D. Only get watercooling if you're an overclocking nut.
Like nhoho said, the system will be obsolete soon. But no worry, spend most of your money on things that won't need to be upgraded for a long time. Such as the case, PSU, and Monitor.
Here what I suggest:
Wolfdale E8400 (Yorkfield is better, but the e8400 is cheaper and good enough for now)
2 gigs DDR2 800/1066 (so you can still overclock a little)
1 Nv 8800GT 512 or 1 Ati 3870 512 (much better cards will be out in a few months anyway)
1 Raptor & 1 400 gig drive
A high-end PSU, top brand. 700w+
A case easy to service and cools well
The best monitor you can afford.
The wolfdale, Ram, & motherboard will be obsolete soon and still very capable for now and doesn't cost much. Upgrade all this next year when the Nehalem comes out - completely different motherboard, socket, RAM.