That announcement is ancient. Well before the push capability was announced and well before developers started making tens of thousands of dollars for making very simple apps. I'm sure it wont be long before they come around.
No, they won't be making an iPhone version, not for a while at least. You read it yourself, they're bound by both the NDA and the GPL. Until Apple lifts the NDA, then, like they said, the terms of the GPL keep them from using all the same libraries. If they can't use those libraries, they need to replace them with their own proprietary libraries. They also can't make money off it either, again because of the GPL. So, all in all, it's not likely that they are going to bring Adium over anytime soon, if at all