Google Calendar Good but Needs Work
The only other problem was that when I attempted to put my wife's Gmail address into the "add guests" box, it listed her under her old maiden name only. This makes it impossible to type her name into the box- I can enter her email though. I assumed this would only be a behind the scenes minor issue until my wife responded back asking why I was using her old name- ouch! Otherwise it seems to be pulling the addresses right from my Gmail with no problems. Besides causing potential marital problems, it does have some other issues too.
Minor hiccups aside, Google Calendar seems pretty awesome. The ability to type in a simple English phrase like "bbq on monday at 8pm at my place" and have it added to the calendar instantly is a very powerful timesaver. The interface is very slick with virtually no loading time for any of the features I tried. This is a significant improvement over Outlook's weak/slow/bulky calendar feature. If GCal were more integrated into Gmail in ways other than just the address book, than Google would have a massive winner here. Just one link to it in Gmail on the left above Contacts would be ideal. There are links to go from GCal to Gmail but not the other way around, from within the respective applications. Ideally it would integrated enough that Gmail's scanning system would read dates/times in your emails and suggest adding this to your Gcalendar, similar to how it asks if you want to map something or track a package.
Google Calendar has huge potential in many ways; if it catches on like Gmail did and with the right application or add-on written, it will devour ad-heavy slow loading Evite-guaranteed. Currently it's an awesome application that I know will help me organize. For free, you have to be impressed.