After nearly a year's speculation, Google Calendar is finally live. From today, all registered Google Account users - that's to say, users of Gmail, AdWords, AdSense, Personalized Search/Homepage, Google RSS Reader and Google Groups - can use the beta of Google Calendar, the latest AJAX-powered application from the Mountain View, CA-based software (including now social software) powerhouse.

"With Google Calendar," Google says at the new Google Calendar log-in page, "you can see your friends' and family's schedules right next to your own; quickly add events mentioned in Gmail conversations or saved in other calendar applications; and add other interesting events that you find online."

The log-in page continues:

• Sharing events and calendars
  You decide who can see your calendar and which details they can view. Planning an event? You can create invitations, send reminders and keep track of RSVPs right inside Google Calendar. Organizations can promote events, too.

• Staying on schedule
  You can set up automatic event reminders, including SMS notifications, and instantly bring up anything on your calendar with the built-in search tool.

Google Calendar is free and allows you to create events in most languages, even though the interface is currently only available in English. (Google says more languages are coming soon.) The browers that are fully supported are Microsoft IE 6.0+ and Mozilla Firefox 1.07+ and, being an AJAX-based application, JavaScript and cookies must naturally be enabled.

Users can import information from other popular calendar applications like Microsoft Outlook and Yahoo! Calendar.