Old iPhone, New iMac

I've had my iPhone for since August and have been syncing with my PC. Just got a new iMac today and am wondering if there is anything I need to do prior to syncing it with the new iMac to make sure I don't erase any info. My main concern is the Calendar on the iPhone is not backed up with my PC, and I'd like to sync the iPhone calendar to iCal. Any thoughts?

Make sure your account on your iMac and PC are Authorized under the same account (Advanced>Authorize Account). Your iPhone will automatically sync with iCal and put all of your stuff in it.

That is 100% correct. I just did it yesterday and it worked perfectly.