Why flash not able to run on iPhone browser? According to Adobe website that iPhone is a different kind of plantform to work on. So it is kind of hard to put flash into it. But the real answer behind this fact is all about money.
Imagine, all the flash content like "pet society" and "online video" able to run on iPhone. Developer can easily put all this content into web and get the end user to log into their website to enjoy it. Who is going to develop software in iPhone? Who going to download music from iTune? Who going to buy game from them anymore?
All about money when you really look into the situation. So, I don't think flash will be enable in the coming future. But eventually when every single device able to surf flash.