I would love Apple to defeat Adobe in this battle, at least on content providers not using Flash for simple tasks like video, which is like driving a Hummer to the corner store to buy a can of soda. No third party like Adobe should interfere with my choice of browser, OS, and content providers. Having the OS and browser handle video and such in a standards-based way is far better: viva HTML5!
YouTube no longer needs Flash and there is a iPhone App for YouTube, even though Google owns YouTube and Google's Android marketing is trying to benefit from the iPhone's lack of Flash support. Also, several major news organizations are reportedly working on Flash free versions of their content for the sake of the iPad. These examples not only show that Flash is redundant for streaming video, but also show the clout of Apple's mobile products (iPhone, iPod Touch, iPad) in pushing content providers to reduce or eliminate dependence on Flash.
I do not know how avoidable Flash is for other uses, like all those annoying, slow loading flashy web-sites, so I can only hope that the desire of advertisers to reach the large and often free-spending demographic that is "iPhone OS users" has the effect of discouraging Flash usage by advertisers as well as by content providers.
But if instead persistent usage of Flash in advertising means that a lot of advertising is invisible on an iPad, while video content comes through just fine, that would be a reason in favor of buying one, not against it!
About the content in itself they do not have to integrate flash, but they will, because of the advertisings needs.
If Apple does not allow it, the competition will.