Google just updated their Gmail app for Android with introducing their newly introduced Priority Inbox. Other features includes:

1. Important actions (reply, star mail) etc actions will stick to the top of the screen no matter how long the mail is .

2. Quoted Text makes it to Android, now you can tap and see the long thread of mail or hide as per your requirement.

3. Priority Inbox.

Please note that these update will require your phone to have Android 2.2 aka Froyo.

FYI :

Update 9/21/10 12:13pm Pacific time: There is a known issue with important actions not sticking to the top of the screen on HTC phones running Anrdoid 2.2, like the EVO 4G and
the Droid Incredible. We are working to address this.

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