I've held / used an iPhone. It's much nicer and smoother than my N95 (interface-wise) but the N95 kicks it over the horizon feature wise. It's fun chatting on Google talk whilst listening to MP3s, task-switching to IRC to check rom releases, and the browser is the best mobile browser I've used (I didn't try the iPhone's browser (safari?) because of the lack of 3G and the relative shitttyness of EDGE.
Plus the N95 has an app to download stuff off the GNUtella network (Limewire), which is cool for mobile songs. And GPS, but is handheld GPS really that useful?
and... the N95 can open office documents.
and the S60v3 OS has a voice synthesizer. So every evening at 9:00, my phone chimes and reads me tomorrows weather forecast.
Basically iPhone: Slick interface, touchscreen, cool factor
N95: Uber functional, awesome camera, MicroSD slot, 3rd party apps, 3G, Video calls, Etc