Maybe these are the guys I need to make the backpack of *my* dreams. I'm currently using a Crumpler Customary Barge, which is good, but not quite there.
I'm looking for an air-travel pack. I want space for two bodies (a D3 plus a D300, and I sure Canon people have an equivalent); space for three fast pro zooms, or four fast primes plus a 1.4 extender, or some mixture of those. Space for the usual odds 'n ends: cleaning kit, memory card vaults, couple of extra batteries and charger.
A laptop sleeve, and pockets for the power supply, power cable and a ten- or twelve-foot Ethernet cable.
And (this is the critical part, that you can't get anywhere): a large dedicated top section for travel gear. By travel gear I mean personal prescription medicine, a jacket, a paperback or two, extra pair of glasses, notebook, pens, chapstick, cell phone pocket, iPod pocket, earphones, etc.
This all has to fit in a bag that is (itself) both light and small enough to fit in overhead bins. I know it's possible, because I went to Iraq with that kit packed in a Blackhawk tactical bag made for medical gear. The problem was that there's lots of useless stuff in the bag (from a photography perspective) and that makes it heavy -- 7-8 pounds on my bathroom scale.
For a travel bag, you're looking for the ability to fit in any overhead, and then carry a lot of stuff a short distance: not a technical pack made for long hikes, but a tote sack made with photography in mind. I found that I did not want a rolling case, because even you're in a city, a rolling case is often awkward; you need to be able to put it on your back. My bags now always have a carabiner on the tote strap, which can be clipped to my rolling bag any time I'm inside an airport or moving both bags on hard surfaces; but much of the time, our of doors, it's easier to carry it.
I tried sending some suggestions to Think Tank, and they thanked me politely -- and continued making bags which would allow somebody to carry 50 pounds of photo equipment onto a airplane, but not even an extra jacket. For most people traveling long distance, this extra stuff is critical -- especially things like prescription medicines and glasses; and anybody who flies internationally knows that you can always use space for stuff like earphones and iPods, especially if you wish to maintain your sanity.
JC
Think Tank Airport Acceleration. I have one, it rocks for air travel. (Some 30 International flights last year), + a DOmke vest to deal with weight issues and annoying airline staff.
I agree it dosn't have a dedicated spot for the 'travel stuff', but I found just dividing off a section using the provided dividers worked a treat. I actually wouldn't want a another 'section' as it would put the bag over size for the airline, or too small to fit the lenses etc.
I generally carry the 'junk' however, int he Domke, fits magazines nicely in inside pockets.