By clicking on event you get a very full editing page where you can specify more details about the event or edit it. There is subject, location, date, author, description, you can add comment, invite guests, create reminders, privacy. This will give you more control on your events to transform your calendar into a meeting website, you can even duplicate events if you wish to.

What I find also great is the integration with Gmail, you can find Add to calendar link when you open a message that contains event information.

Google makes it easy for you to keep track of your schedule. Just like we do with addresses and package tracking numbers, Gmail displays an Add to calendar link when you open a message that contains event information. This way, you can easily add the event to your Google Calendar.

There is also a mobile version available currently for limited US mobile providers : AT&T, Cellular One, Cincinnati Bell, Cingular, MetroPCS, Midwest Wireless, Nextel, OmniPoint, Qwest, Sprint, SunCom, T-Mobile, US Cellular, Virgin, Western Wireless. You can also receive notification by SMS, but there is no details in the website about pricing and the rate used, so you have to contact your mobile provider to ask about these details. But it will be interesting if there is a mobile version accessible in the same way as Gmail for mobile, or Google news for mobile.

Overall the products looks really great and very suitable for me, bringing all useful features to manage a calendar online. Personally I don't move too much from my office but people that need their information accessible from everywhere they'll find in Google calendar an excellent tool specially if they can use it from mobile too.

For more information http://www.google.com/calendar/