The centimorgans are the most important. For instance the centimorgans of my son are 3425 (not 2425 as I put originally, a cousin's daughter 423, my half 2nd cousin once removed 66, however, Ancestry shows her as my 4th cousin as the average number of centimorgans is similar for half 2nd cousin once removed and 4th cousin. Obviously, if I hadn't already known this person I could have got confused trying to find a 4th cousin who didn't exist.
There is a shared centimorgan (Cm) Project with charts showing the relationships etc. if you go to:
http://www.rootschat.com/links/01mwq/some of you may find the information interesting.
