This is correct. If you use Google.com/Calendar to handle your calendar, you can do this. It will then sync down to your account.Well, my Incredible hasn't shipped yet so I can't speak to that, but you can do this on Google Calendar. That should sync down to your device.
I too haven't been able to find a way to set a bi-monthly (every other week) appointment. I don't use Google calendar and don't plan on it since I use Outlook and sync with my Inc. I've been trying to find a solution to this too but haven't come up with anything yet.
Anybody else have a work around?