Google has dropped the iCal bomb. That's right. Buh-bye third party intermediaries, hello built-in Google Calendar support for Apple's open source CalDAV standard:

The Google Calendar team is proud to announce the public release of our support for the CalDAV protocol. You can now use Apple iCal with your Google Calendar, so you can work even when you're offline, sync almost instantly, respond to invitations from others and see the free/busy data of your friends and coworkers.

You can get both the setup program and the download from Google code source. (Now if we could only get some similar Google love for CardDAV as part of a Google Contacts revamp...)

If anyone has a chance to try it out, let us know how it works for getting your gCal into MobileMe or onto your iPhone (I'm -- right now very sadly -- transitioning to the HTC FUZE for the Round Robin, so let me live vicariously through you!)