Don't forget Mark Spitz
My local paper had a nice piece on this. They pointed out that Phelps has marginally triumphed over Spitz - 8 Golds vs 7.
However:-
1) Mark Spitz acheived his swim wearing good old fashioned "budgie-smugglers" (bathing trunks), NOT a high-tech super-slick body suit
2) Phelps is clean-shaven and crew-cut whilst Mark Spitz had to drag a 1970's haircut along...
3) ...AND that epic fuzzy-bear moustache through the water!