Google today launched its long-awaited web-based calendar service, in beta, reports PC World. Google Calendar, speculated about in the blogosphere for more than a year, was in development for "several months" and is, for now, integrated with Gmail, according to Carl Sjogereen, a Google product manager - "but you can imagine integration with a number of other Google properties," he said, hinting at integration with Google's personalized homepages. Google Calendar users will be able to schedule events directly from Gmail messages or by using a QuickAdd feature. Google Calendar can then send out email invitations to others and event reminders and change notifications.

Users can also search for and then subscribe to publicly available calendars - and then import that information into their own calendars. They can also share calendars via RSS.

Google's calendar is ad-free, but the company hopes to profit by having users spend more time with Google and so see ads on other pages, according to USA Today, which quotes Sjogreen as saying the company launched the service because Google users "wanted to see a new approach to calendars. Our mission is to organize the world's information, and one piece of information people care about a lot is what they're doing every day."

In at least one aspect Google is behind Yahoo and AOL - allowing users to sync information to portable devices. Google says it will add that functionality in the coming months.