The big deals:

If I bought a ticket that allowed 2 carry-ons, and now I'm only allowed 1, they've changed the rules and I want a partial refund.

If I decide to fly (lets say) Northwest to Vegas and connect to America West to LA (specifically using two different tickets to save hundreds on inflated airfare) I would need to leave security, retrieve checked bags, have them inspected again, and likely miss the second flight.

If I do check my bags, and the airline makes a temporary diversion to another airport due to weather or something, I can remove my carry-on bag and make alternate arrangements. (This happened to me twice this year. On a business trip to Houston. The plane landed in New Orleans. I was with an associate who checked and received his luggage only after the business trip was over. I had mine with me.

United just lost a case in court where they tried to impose their carry-on limits (this time in size) on other airlines. If it is my choice to fly a carrier that allows 2 bigger bags, or if I choose to fly in First class for that benefit, how can the FAA sumarially decide that this free-market factor is no longer to be considered?

And finally, as almost everyone here really knows THIS IS NOT SECURITY. THIS IS THE ILLUSION OF SECURITY. GUNS, KNIVES, LIQUIDS ARE PASSING THROUGH THE SCREENERS CONSTANTLY. EVERY INDEPENDENT TEST OF THE SYSTEM HAS FAILED. LIMITING CARRY-ONS WILL DO NOTHING FOR SECURITY, IT WILL JUST KEEP MORE PEOPLE OFF PLANES AND FURTHER WORSEN THE ECONOMY.

If they were serious about security of bags, every bag should be hand inspected, carried to the plane by the passenger, loaded into the cargo hold with the passenger wittnessing it, and retreived in the same way upon landing (much like a small commuter plane or bus). Then I'd put all my bags in the cargo hold, knowing I'd get them back.