I can tell you I am extremely happy with my N8. I can't tell you how it stacks up against the iPhone because I hate everything to do with Apple and avoid tainting myself with their products like the plague.
So, I've never used an iPhone, and therefore couldn't tell you. The N8 has a few little flaws that will be ironed out in the next Firmware update. For some reason in landscape mode the keyboard always double spaces between words, when using the web browser only. Which was annoying as hell for FB etc. but I downloaded the Swype app. and not only has it fixed it but who the fuck needs to type when Swype totally kicks arse.
The three different home screen thing is an awesome way of having everything customised to your liking and quick to access.
My main hate is that MobiPocket have not updated their program for the N8 so it will not work and I had heaps of eBooks I haven't read yet. Also, as of yet there is no alternative eBook reader for the N8 so far, and reading eBooks is one of the main functions I use my phone for.
This is the main problem with the N8 I guess. If you want apps coming out of your arsehole you'll have to wait a while, but the Ovi store is gearing up and I think the N8 is the phone that will attract app makers etc. to the store.
Oh and the camera is everything it's hyped up to be.
If I use the internet constantly, play games and music, and generally dick around my phone will be ready for charging when I get home after 9 hours at work, so not sure how that stacks up against the iPhone, but reviews I've read said the battery life is longer.
Multi-tasking is an ease and the phone can run quite a few different programs at the same time without screwing up.
Before the N8 was announced I was pretty much ready to switch from Nokia to HTC because Nokia hadn't released a decent phone in my opinion since the N95 8GB and N85. I'm glad I hung out for this one though and didn't switch to the google phone. If nothing else, I use my phone a lot to take photos at work and the camera is a dream.
I suck at photography but in the right hands the hardware would be amazing. Some of my poor attempts (I see things all the time at work that I want to capture):
