Anyway, I heard that it was equally loved and hated by the early adopters.

For example, my friend didn’t like the way the iPhone syncs with iTunes. The iTunes won’t let you drag any song to the iPhone, as it requires playlists.

From what I heard, the iPhone Activation was a breeze for existing Cingular/AT&T customers. As for switchers, they might have slight resistance from their current providers (Sprint, T-Mobile, Verizon, …….). Honestly it is somewhat expected, they don’t want their customers to switch.
If I’m not lazy, I’d write more here. I’ll update this entry later.