Hmmmm...hard to diagnose exactly what is happening here.  Since it is a 2007 car, I recommend that you call the dealer from which you bought it and ask them for any advice. It could be that you are still in the "break-in" phase of the new car, but it's better to be safe than sorry.

There were a handful of the new 2007 Toyota Camrys that had a defective transmission.  IF yours was one, you should have received notice from Toyota.  Double check with your local toyota service department to ensure yours isnt one.  If it is, Toyota WAS offering either a Full reinbursement, or a simple exchange for another brand new one (regardless of your 9000 miles)

The newest models of Toyota do not have a cable on the gas pedal, it works by an electronic sensor. See if the dealer can check or replace this. "Break-in" would have nothing to do with this, it should go when you hit the pedal from day one.

That has happned to me once or twice on my 2007 LE 4 cyl. The first time, I planted my foot down on a freeway onramp and nothing. Just when a Highway Patrol car was right behind me. Eventually it kicked in, but I thought for a moment the engine had died. Since then I get some lag from time to time but not as severe. Now when I know I'll need power I shift down to 3 or 2. I've been reading other forums, it's probably the transmission and/or engine electronics taking too long to compute what to do and the phenomenon precedes 2007 models.

Thank you for your answers, after the second time at the dealers, it happened to them on a test drive, they reprogramed the cars computer and it stopped for awhile, but is acting up again now, not as bad as the first time, and it seems to happen after left turns, long delay, then it goesI've almost been rearended, if they can't correct the problem I'am going to get rid of the car.

HAVE A NEW 2007 CAMRY I HAVE THE SAME DELAY SHIFTING PROBLEMS I WILL TRADE SOON IF IT CANNOT BE RESOLVED.

I have the probablem as well - drives me crazy. If I could I'd get rid of the car.