That's what everyone says, and it's not exactly what most want.
On my BB, I was updated when I'd receive a notification. Of course it used an email system but It would delete the emails from the server when i'd get the notification on the phone.
I really don't want to have to open my gmail app, then follow a link to the mobile site when it could easily be all wrapped into one application. it's very annoying.
The fact that I was getting a real Notification from my phone and not the email, was excellent.
The UI on the facebook app is awesome. But not having an inbox & real notifications that I don't have to manually look for would make it amazing.