Here's the official list of participating hotels:

http://www.hilton.com/en/promotions/...ist_FINAL3.pdf

I was just under the mistaken belief that all Hilton properties were participating (I'm a pretty recent HHonors gold -- I'm used to the way they run things at Starwood).

Clearly, if your hotel is participating, and you're not spending several nights there, the Southwest promo is a better deal than "more points" if you have use for Southwest credits.

Switching back and forth between points and mileage credits based on "the list" IS the way to go, but that's REALLY staying on top of things!