Apple unveiled the much awaited version 3.0 of the iPhone OS on March 17th. Amongst the myriad of updates and additions are:

Cut/Copy/Paste
MMS
Push notifications
Landscape orientation for all apps including email
Global search that includes mail
A2DP – Stereo Bluetooth
Turn-by-turn navigation now allowed in the App store

The big addition for wifi-phone applications is the inclusion (finally!) of push notifications. To see why, check out the About section of wifitalk.