3G Connectivity on the iPhone
Before buying an iPhone, I researched extensively on what existing users were saying about it on the internet. I got a mixed response. Many people were complaining about its 3G connectivity, and given that WiFI is not always available were I am so 3G connectivity was a major issue for me. I went for the iPhone anyway, and after using it extensively I've found out that the 3G on the iPhone works very well for me. I get nearly 1Mbps speed from my home.

Other issues included complains about lack of multimedia capabilities like MMS, video recording etc. Those issues are real, however my prev. cell phone was the N95 a leading multimedia cellphone from Nokia however I've rarely used those features. So these are not a big factor to me.
The thing I think that is revolutionary in the iPhone is the applications ecosystem, no other platform has such a rich application ecosystem. The whole device is not a phone, its a generic computing device. The phone capabilities are encapsulated in a single application, just as web browsing is encapsulated in the Safari application. This concept itself I think is game changing.