That is to say, our inboxes are getting smarter and smarter. Serious tools are being built to help us direct and manage what was once just a chronological flow, which people dammed with inadequate organization systems hoping to survive the flood. (Remember all the folders in desktop email clients!)
Unfortunately, while inboxes get smarter, people get lazier. It's always been a tug of war but the last 5 years has resulted in a dramatic shift where I need to filter out bacon from friends and family a lot more aggressively than ever before. I think the future Alexis paints will be great: junk from friends and family moves to services like Facebook (where I would never see it). I think it will take at least one more generation to see that happen.
Even in this light, email is my favorite communication tool for all of the reasons listed in that link. It's the perfectly balanced combination of power, ubiquity, and simplicity.