From the video, it looks like they have a Bayesian-style mail filter, but instead of applying it to find spam, they apply it to find important mail. This is no

From the video, it looks like they have a Bayesian-style mail filter, but instead of applying it to find spam, they apply it to find important mail. This is not too hard to set up; the tricky bit they've automated is analyzing which emails are read and replied to, as opposed to just which ones are marked, so it's more automatic.