The Twitter iPhone app now comes with a clever little feature: Notifications for @mentions.
This means that whenever someone you follow mentions you on Twitter, you can receive either an SMS—just as you would with Direct Messages—or a push notification on your iPhone. The push notifications will require the latest version of the Twitter app which
should be available today is available now. [Twitter]
Update: Turns out that the app allows you to set whether you want to see @mentions from only folks you follow or from everyone. Very clever.