Great read, and I'm expecting this to happen sooner too. Think it something like -- the core-emailing is there within gmail, but extend the functionalities via services. Some external app uses to build services on top of emailing. Something like -- Hootsuite on top of twitter, Hootsuite manages and adds value by its own apps. Think: we have Gmail powered apps? A link on top like: my-installed-apps -- to easily naviga…
I'm working on stuff like this but from the ground up. You can't get any meaningful innovation until you can allow people/devs a way to access the system at a deeper level than Gmail will allow.
Build and think platforms and API's. Not consume API's :)