Note: I found out you can use Skype and fring on an iphone without a headset, and you can actually use it to save you money if you have iphone and At&T already !
OK There are tons of articles about this, I just want to do a quick wrap up of what I found out. If anyone wants to try and see how much it will save them goto Skype & www.fring.com.
Pros of having Skype/Fring on iPhone (even if you have the At&T Network )
1. Make calls without using your anytime/rollover minutes where you have Wifi (I was told that it also works with their data plan, I want to see it before I believe it, but still worth trying).
2. Text message all your friends that use Yahoo, Skype, googletalk, msn, ICQ, twitter, SIP, AIM right from your iphone with one app ! (Fring)
3. Get Push notifications through Fring so people can message you while you are on another app
(settings can be changed accordingly)
Cons of having Skype/Fring on iPhone
1. Its doesn't blackout like normal calls from iphone so it also uses more battery power !
2. Can't call another iPhone from iPhone using Skype, not sure why?