What equipment do you generally fly with? I fly extensively as a professional photog and run a well traffic blog intended to make life easier for flying photogs at www.flyingwithfish.com

Depending on the gear you can back door into a bag. Generally a full size roller or full size backpack loaded with camera gear is not considered a 'personal item.' I have successfully argued that a Pelican 1514 was my 'personal camera bag' with Continental on an LAX-IAH flight, when my carry-on was a fully loaded Think Tank Airport Addicted (flying with 4 bodies, 8 lenses, 4 flashes, 3 compact lights stands etc etc etc). I'm pretty sure they just conceded due to the DL Plat and NW Gold status rather than due to the rules.

Look into a low profile backpack that is highly configurable. If you prefer a shoulder bag, look into one that more closely resembles a brief case. Visual deception goes along way. If you fly with a lens/body combo attached, detach them to maximize your packing space effectiveness (and to protect your gear!). By being versatile in how you pack you open up many bag options.

Happy Flying

-Fish