The truth of this matter is probably somewhere midway between the extremes. It is not really fair to say that Megaupload has "no U.S. presence" if it has assets in the United States that the feds could freeze. (The feds, without the cooperation of a foreign government, cannot freeze assets outside the U.S.)
On the other hand, it appears that deception and misinformation in the obtaining of the warrants might mitigate in favor of the accused here.
Oh, what a tangled web we weave, etc....
It is doubtless that Megaupload was used by many for illegal purposes, but does that make Megaupload liable for all illegal activity on their site? I don't see where precedent for such liability exists in the law as it stands today, and it would be dangerous to establish such precedent, as it would have far-reaching and unintended consequences.
I only hope our judges do what's right for the law, and right for the body politic.