After reading through the thread it seems they are rejecting apps because a piece of the Dropbox SDK breaks the App Store guidelines. They are not simply rejecting Dropbox integrated apps.
It's well known that you cannot link the user to make a purchase outside of the iOS ecosystem. It was a huge issue with the eBook apps last years.
I'm not saying I agree with Apple's stance on that but they are not rejecting apps which use Dropbox because they don't like Dropbox. Dropbox is breaking the rules and as soon as they fix that (it seems they already have) there will be no more problems.
It's well known that you cannot link the user to make a purchase outside of the iOS ecosystem. It was a huge issue with the eBook apps last years.
I'm not saying I agree with Apple's stance on that but they are not rejecting apps which use Dropbox because they don't like Dropbox. Dropbox is breaking the rules and as soon as they fix that (it seems they already have) there will be no more problems.