Cena - 9 World/WWE Title Reigns. 11 if you include OVW and UPW.
Edge - 10 World/WWE Title Reigns.
Flair - 17 World Title Reigns.
I seriously doubt anyone now could do that. As for the Miz being a "transitional Champion", he has kept the belt for 80 days so far. When he gets to Wrestlemania, he'll have that belt longer then any of the Rock's individual reigns. Infact, at Wrestlemania it would be 133 days, the same length as Eddie's first, Cena and Taker's second, and Bret Hart's third reigns.