Five months after originally posting the thread, and reading countless reviews of various backpacks, I followed Schnee’s advice and picked up a Kada R-103. The Kata was a bit pricey, at $185, but not much more so than the stuff that Lowepro & Tamrac offer.
Actually, he suggested the -102, but I also needed to be able to carry my laptop, and the -103 is the same as the 102 with the addition of a pocket on the back that Kata claims will hold a 17″ MacBook. Honestly though, my 15″ is a little snug, so the 17″ would probably be pushing it.
The bag looks pretty much indestructible, and hold everything that I used to carry in my camera bag and my laptop bag:
Nikon D-50 w/ 18-55 (probably 80& of my shooting)
Nikkor 50 1.8
SB-600 (I couldn’t justify the extra $150 for the SB-800)
MacBook Pro 15″
3 2.5″ HDDs
Creative Zen Vision:M
lots of cables.
Various color ABBCs
I still have roughly half of the space that surrounds the camera available for other stuff as needed, and hopefully more glass before too long.
So, thanks Schnee, now I can get out and shoot more without feeling like my arms are going to follow off or my shoulders are going to collapse.