Google recently rolled out the beta for their new Priority Mail feature for Gmail. I got it now, and it seems very promising. Gmail will now automatically organize important email for you on the top, and unimportant ones at the bottom. It's a feature nobody else thought of until now. This breaks away from the conventional way of organizing a mailbox, by the received date.
If you get this little link in the top-right corner, you can use Priority Mail:
Now, click it, and it will display a pop-up, like this:
You can choose to see the little video, which explains the concept of Priority Mail. If you want to try out the new mailbox feature, you know what to click.
If you choose to try it out, you'll be shown a little box, with some of your read email. Gmail will ask you to choose which ones are important for you and which are not. Depending on your input, it will slowly learn what types of email you think are important.
Now, when that's done, Priority Mail will be set up for you, and the page will refresh. When Gmail is done loading, lo and behold, you have got a huge revamp.
The little notification says that the new feature is ready. And you've got an email from Google that explains the new features and controls. You can change settings for Priority Mail from your Settings.
Overall, your mailbox will look completely different. There will be a new section on the top that shows you the important and unread stuff. Then there'll be a section showing you your starred email. There's a third section, showing everything else.
Now, to use Priority Mail properly, you should mark your email as important or not. Then it will learn from your choices which email to classify.
The left pane has also changed. There's a Priority Inbox link also. The number there will show the number of important and unread email for you.
Good luck with the new Priority Inbox.