hmmm...so are the deals different across the US? I'm in Texas and when I type in my zip code it comes up as $189 with an upgrade, not $129. And you are right, the $100 gift card cannot be applied at the time of sale, the site just words it really loosely (but that's marketing for you).
PS, just noticed that it is "backordered" so I wonder if a few people were able to get this deal, and they'll shaft the rest of us...
Also to someone's point above, you can trade in your old phone. But the avg. trade in value for my samsung moment is $53.71 (I think i'll keep it for that amount)