Killer App for Events?

Dare Obasanjo asks Where is the Killer App for Events?

The killer app for events is email.

I use Yahoo! Calendar, and I've been using it for years. I enter things like birthdays, anniversaries, and other recurring events I want to remember, and every year, I get an email a few days before the event. Email is the event notification.

I don't need any more than this, nor do most people. If you're a busy executive then you need a calendar where you can book meetings and people can schedule appointments with you; but all most people need is a reminder that "Lost is on TV tonight".

Maybe that's all we need to kickstart calendaring: A simple XML format that describes an event, and a web service standard that a calendaring service can implement to say "Add this to my calendar".

With this little bit of glue, sites could add "Add this to my calendar" links that would add it to my Yahoo! calendar (or whatever calendar) so I could get my event notifications. That's all I need.