Google Calendar was announced yesterday. I’m not sure why it’s better than other calendars yet, but I’m sure I’ll find out.
Update: I just took a quick glance at some of the features.
Con: no multiple reminders for a single event (one of my pet peeves is that amazon got rid of this feature)
Con: only a 1 week in advance reminder window
Con: no recurring events
Pro: Calendar sharing
Pro: Multiple user author permissions
Pro: Multiple calendar creation options (home, work etc.)
Pro: Natural language appointment scheduling
Pro: Gmail integration