new spare battery rules for u.s. travel

from the geniuses who determined that only a one quart bag full of 3.5 oz liquids is permitted, comes new rules about bringing lithium-ion batteries in united states travel.

what seems odd to me is that the restriction is on checked baggage and not carry-on luggage per se.  from the site, it indicates that a spare battery is something not installed on the device.  and if you wanted to bring a spare lithium ion battery along, you have to put it in your carry-on luggage as putting it in your checked luggage is forbidden.  what?!

what concerns me (as i don't believe this will affect my day-to-day travel...i don't travel with spare batteries that much.  but i've recently gotten some camera equipment that has a lot of batteries: 2 for the camera, one huge li-ion for the light equipment.  and the bummer is that all of it won't fit in a case that is carry-on size...so it has to be checked.

so now the question becomes...what happens when you leave your luggage with TSA to be processed and you walk to your gate...do they make a discovery of a battery and then decide not to send your luggage?  take out the battery and replace it with a note "sorry, we have your battery now"?

brilliant.