Push notification has been around for a couple of weeks now, although there are still plenty of publishers integrating the technology into iPhone and iPod Touch applications.
One of those is Yahoo, their instant messenger application has been updated to version 1.21, although the content and form are identical the difference is that it can now push an instant message alert and notification to you even when the messenger is closed.
It also shows you how many missed messages you have, along with a nice chime to alert you when a message comes through. The latest version keeps you connected for two weeks at a time again even when the application is closed. Only one problem Yahoo has not yet enable simultaneous sign ins, so the second you go onto YIM from another location you will be booted off of your iPhone. Source - cnet.com
