After owning all 3 generations of iPhones I decided I needed a change so I sold my 3GS and purchased the Nexus One on T-Mobile.
I originally made this thread to explain why I was regretting switching from my iPhone 3GS to the Nexus One. After comments and suggestions from other Nexus One and Android users I've fixed the problems that were plaguing me and have grown to love the phone.
NEGATIVES (Now with solutions!!)
1) On the iPhone, when you answer a phone call and put it to your ear the screen goes black to save battery. But the instant you pull the phone away from your ear the screen lights back up so you can hang up the phone or look at Google Maps or something. The Nexus One lacks this feature, and in order to hang up you have to hit the button on the top of the phone then swipe your finger to unlock the screen before you can hit the "end call" button.
SOLUTION: Simply install an app called "Shake Awake" and the phone will now wake back up as soon as you pull it away from your ear, allowing you to hang up just like you would on the iPhone.
2) There is no built in visual voicemail. I forgot how awesome this feature was on the iPhone because it eliminated having to call your voicemail, enter a passcode, then hit "7" to delete and "9" to save. With the iPhone you can pick certain voicemails to listen to while deleting the rest, in any order.
SOLUTION: *Thanks llustig* (requires Google Voice) You can set your phone's voicemail to be received by your Google Voice account. When you receive a new voicemail just click the Google Voice icon and it will display your Voicemails on the screen and even translate them for you so you can read them without having to listen to them.
This feature is even better than the visual voicemail built into the iPhone because you can go into your Google Voice account on your computer and read/listen to your voicemails without even using your phone.
Glad you found solutions to your problems. However, my stock Nexus One does what your third party app does for the first issue. Not sure why it's different.
The Nexus One rocks though doesn't it? Best phone I've ever used.