National/Alamo and the other current on-airport rental agencies, as well as two that are currently off-airport, have all signed on to be tenants in the new BUR rental car/intermodal transportation facility -- construction is set to start soon and continue until December 2012.
No word if there will be an Aisle setup for National/Alamo, but it should at least allow a larger selection.
The bad news is that the PFC is going to increase when the new facility opens, but you could probably have guessed that.