Well, all this discussion finally prompted me to sign up. Also noticed that a place I'm often at for lunch has signed on (the first one I go to with regularity to be a part of this).

I can't see geting a lot of miles under my patterns, but this looks useful for topping up "orphan" miles in 2 or 3 of my accounts to levels that could get something like a Hawaii interisland award.

(BTW I used to use orphan miles for mag subscriptions, but with sites like Bestdealmagazines offering $3 and $4 subscriptions, that's gone a bit by the board).