I just found out. You can get $100.oo on board credit if you own 100 shares or more on a 7 day cruise on sailings through July 31, 2006. But I heard they usually renew this every year. And the cruise has to be be booked by 2-28-06.
You are suppose to let the TA know this, when you book. I called Carnival and they gave me this fax number 305 406 6477
You let them know, booking # ship and sailing date, along with proof of ownership.
I just faxed my info, so I do not know if I am going to get it yet, we sail 3/5/06