Google Calendar has just launched today. It seems like a decent, clean calendar interface that is very smooth and easy to use.
You can have multiple calendars if you want and you can search for multiple calendars across the Google Calendar database. This will allow you to keep up with your favorite sporting events (if someone makes it) etc and you can add that as one of your own calendars and look at it anytime you want. You can also look at your friends' calendars as well as holiday calendars. Also, you can set up phone notifications for your most important events. Google has not specified whether it is via text message or not but it seems that way. Furthermore, you may import any calendar if it is in the iCal or CSV (Outlook) formats.
From what I can tell there is little, if any, intergration with Gmail which is a huge disappointment that I'm sure everyone will gripe about.
Look and Feel: 10/10
Ease of Use: 10/10
Integration with other Google products: 5/10
*I apologize for this story not being able to read writer earlier in the day when I first posted it (10 AM). I was not at my personal computer and for some reason it would not work (Just look at how I had to use IE in the pic).