The guys from Divmod were here at PyCon and today the gave a little talk about their service.
The basic functionality of their site is to provide a way to collect your email, rss, calendars, etc. into one place and they'll catalog it for easy searching and relating the information together.
They also provide VoIP service and can keep a log of your calls which is tied into the same address book information from your email, etc. Apparently they'll soon be able to let you specify rules about different people trying to contact you, so that email or calls from certain people are important and always go through, or others can get directed to voice mail. This can even be set up to be on a schedule so that people could only get in contact with you during business hours, or other similar rules.
The thing that I found most interesting is that they're working on determining information about references to dates for scheduling appointments. They claim that they'll be able to pick up on phrases like "next Thursday" and determine prompt you if you want to create an appointment about the meeting that you were discussing.