I think that's part of the big argument with the iPhone; everyone thinks it's so revolutionary when most of its features have been available on previous models for years already.
The N91 may not have 850, but the iPhone doesn't have support for 3rd party apps. It's always a tug of war with phones, and thus far, none of them are the end-all, be-all. But, for the argument, the iPhone is NOT the first phone with an 8gb HD. Same goes for the 3.5mm headphone jack in the same category.
If I had to find ONE thing the iPhone has brought to the mobile world as "revolutionary" , I'd have to say its unique screen resolution (being both in a high resolution and a goofy size) and the its Apple formatted touch screen interface. Even the UI, however, has been cloned and done already on a Windows Mobile device if you read around a bit.
The iPhone is not revolutionary, and I'll argue against any other feature that one might bring up to suggest it is. In the grand scheme of mobile phones, if you do your homework, you'll see that the iPhone is just another Sidekick, at best; a phone everyone thinks is fun to play with, but falls WAY too short when it comes to a powerful media capable smartphone.
I like the idea of waiting until the next batch of phones comes out, as I've posted in another thread, but buying the iPhone in the meantime is just a waste of money.