Regarding timing belts - I'm 99% sure that the distributor is running off of a gear on the left hand camshaft. If the belt was broken, the distributor wouldn't turn.

Also, I did a little research and found http://www.gates.com which has a timing belt guide that shows interference engines. The 3VZE is not.

Anyway, tonight I verified that the air sensor was OK and the ECM was seeing good signals. It was interesting to hear the fuel pump come on when the ignition switch was ON and the air volume sensor door flap was pushed in a little bit by hand. That seems like a quick and easy way to check that the EFI relay, Circuit opening relay, fuses, air sensor and fuel pump are all working if you're ever in a similar situation. Between that test and a spark test from the igniter, it seems like you can pretty quickly eliminate a lot of possible problems.

Then I decided to pull out a plug and double check that I'm really getting a spark (perhaps a timing light isn't a good way to check this). When I pulled off the first wire (carefully - I know the right way to do it!) it broke off from the plug connector with no real force. These are "Original Engine Management" wires that I got from BAP. I'll replace them with true OEM parts and try again.