I had a...

Sagem > Nokia 3210 > Nokia 8210 (accidentally smashed it in a fight with sister.. i was young... lol) > Siemens M55 aka Scorpion (I LOVED THIS PHONE! It had a funky "moo" sound whenever an sms came in) > N-Gage QD (after accidentally dropping Siemens out of college window ) and finally > iPhone

Initially i missed the tactile feel of the previous phones.
But after a week or so, i got used to the iPhone. Its truly an amazing phone. Its intuitiveness is unrivaled.
And the App Store n 3rd party apps.. makes its technology to die for.

In short, i dont miss my old phone one bit. But i keep it handy 4 my secondary number