As expected, Transformers: Revenge of the Fallen won't have the word of mouth to hang around Star Trek style, though its megaton opening has already made it the year's top grosser. It fell just over 60% in its second weekend to virtually tie with Ice Age: Dawn of the Dinosaurs' bow with $42.5 million in the estimates, though the final numbers will surely break the deadlock.* A 60% drop is by no means unusual for a movie that opened to well over $100 million, so don't think the drop is a badge of shame or anything. Mr. Bay is still very, very happy.

Dawn of the Dinosaurs, meanwhile, collected $67.5 million over the five-day holiday weekend. That's not a bad showing either; its franchise predecessor collected about that much in its first three-day weekend, but it had virtually no competition at the end of March in 2006. The third film's numbers are likely enough to keep the franchise alive.

I was impressed with the showing for Public Enemies, which really leveraged its cast and gangster movie hook to the tune of $26.2 million over three days, and $41 million over five. Michael Mann's current top box office performer is Collateral with just over $100 million; it's unclear that Public Enemies, which is lengthy, difficult and dark, will be able to hang on long enough to toy with that number. But I think it's already earned a minor victory.

*Edited to note: The deadlock was broken in favor of Transformers, $42.3 million vs. $41.7 million.

The full top 10 after the jump.