Out of curiosity I pulled the data on the top 1000 movies of all time by revenue. As you can see, and perhaps as you suspected, the long-tail/power law distribution remains constant with blockbuster movies too.
What I found most striking as I mined through the list was the sheer number of computer animated movies like Finding Nemo, Kung-Fu Panda, and the like that were at the top of the list. Similarly, any film starring Will Smith—even Hancock—was pretty near the top.
If I were running a studio I’d try and bankroll as many CGI movies starring Will Smith as I had budget for.