I'm sure it's been pointed out in other parts of the forum but when you connect at first to your mac, nothing will happen.
-go to the phone, pull down the window shade, (the top black bar with the sync and usb icons)
-click on Ongoing-USB Connected'
-a pop up will come up with the options MOUNT-don't Mount. (click Mount..who wouldn't)
-Your Eris will show up as a unnamed drive!
You can drag and drop stuff directly to the drive or use Double Twist to add music, pics or movies. Double Twist tends to take a little longer, but converts movies to an acceptable format for your phone.
for the calender syncing. add your Google account to your iCal!