First Impressions: Google Calendar.
CREATE EVENT
1. When you enter a new event, after typing in the description, you have to use your mouse to click the 'Create Event' button. It'd be easier if you could just press [Return]
EXPORT TO iCAL?
2. Looks like Google Calendar has in import function for iCal but not an export to keep your iCal up to date with online changes.
MULTIPLE DAYS
3. Scheduling and viewing multiple day events is easier and display more nicely than iCal.
ADD TO MY GOOGLE?
4. My personal Google page doesn't know about my calendar and I don't see a way to add it via the Add Content function.