Yotify makes use of what it calls Scouts, which are kind of like Google alerts. They are also very close to services described more than a generation ago by Frederik Pohl and Arthur C. Clarke.
Yotify offers sophisticated alerts that will allow the user to request very specific kinds of information from sites; some websites are more tightly tied into Yotify than others. For example,
One potential use case for Yotify involves LinkedIn, which is included among the site’s supported services. An executive (or headhunter) keen on recruiting a particular engineer could use Yotify to monitor the user’s LinkedIn profile, so they’d know when that person’s employment status changed.
Also, Yotify seems to put intelligent agent use into a more social context. It appears that multiple people can share a Yotify Scout. Also, queries can be broadcast to sites like Facebook and Friendfeed, and Yotify will catalog the responses.
...Morgan's list contained fifty items; he had heard of people with hundreds. They must spend all their waking hours battling with the flood of information, unless they were like those notorious pranksters who enjoyed setting up News Alerts on their consoles for such classic improbabilities as:
Eggs, Dinosaur, hatching of
Circle, squaring of
Atlantis, re-emergence of
Christ, Second Coming of
Loch Ness Monster, capture of
World, end of
About ten years earlier, Frederik Pohl put it in the context of a highly sophisticated verbal interface that would help the user set up an Interests Profile.