Any Dealer who is smart should happily take a deposit and guarantee you the first allocation for an '09 V.
I did this with the 2008 CTS, and once the ordering guide became available, I called everyone who had a deposit and invited them to come in and build their car as I order it, exactly the way they want.
Some people will pay a premium to be the first on the block with a new toy- it happens every time there's a launch of an exciting new product.
People put deposits on cars all the time to be first, just like people paid $10k over sticker to get a Shelby Mustang knowing full well that in 6 months they'd be everywhere. Is sure as heck wouldn't, but I deal with plenty of people who would (and do).