After getting no answers to this, I decided to open a real problem, so I went to Support.Apple.com and within a few short clicks, Apple called me.
I accidentally hung up on them, and they called back in 2 minutes.
I then waited in the queue for a few short minutes. The person who answered, understood my problem and transferred me to the iCal department where I waited another 15 minutes.
The iCal department then did some research for 10 minutes, and came back to tell me that, unfortunately, iCal is working / not broken. I disagreed, saying that this is my business computer and not being able to send meeting invites to anyone not using a MAC is insane.
The support guy suggested I tell the developers directly, via http://www.apple.com/feedback/ical.html.
He suggested that you all do to. The more people who feedback, the faster we'll get a fix!