As far as promo's go, I would say Flair was better overall at delivering them, but Rock's entertainment value cannot (still today) be beat.
Just comparing the Rock vs Cena exchange for the last few weeks... Cena makes me cringe in embarrassment. He is so out-classed by the Rock.
I lost interest in wrestling about 4-5 years ago, probably around the time all the stars from the 90s went off in different directions. The writing, characters, and performances just got uninteresting - likely due to the lack of competition... they beat WCW, ECW and nothing to really compete against (TNA doesn't count). HBK, HHH and Undertaker alone couldn't carry the company any longer.