Yes, I had heard a news report about that. But all in all I do not see it as being significant.

Best I can recall it like

2012 to 2013 the increase is from 679 per year to 1100 per year.

That's not exactly telling to me. Sure percentage wise its a large jump, but then percentage wise to total population... its nothing.  More non-news.  

http://online.wsj.com/article/SB10001424127887323977304579002780562003814.html

We have to see "leaving" and "coming" from and to any country in a modern light.  It's not the same today as it was in the 1800s or before, when a person left his home country to emigrate to someplace else, forever discarding his former home, and never returning to his country of origin.
With most of the world being no more than a 12 - 14 plane ride away from the U.S., an expat today doesn't forever discard any hope of coming back, usually often.
My grandfather came from Switzerland.  I've been to his village, and to Switzerland three times.  I do feel a little "pull" to the country of my ancestry.  If I could afford it, which I never will, I could see having a second home there, and spending summers in the same village from where my grandfather came.  I speak enough German to get along, and if I were there for any considerable time, I'm sure that my language skills would improve quickly.
Does that mean, again if I could afford it, that I would "quit" the U.S.?  No way.  
With today's transportation, having a second, or even primary home in another country isn't that much different than a person from Minnesota having a winter home in Florida.

I am not convinced. To be sure the very rich, and those with a need/desire are leaving the country and taking their wealth with them. But I think that, with regards to the article, there are many of more modest means, that had used the old laws to live in one country and either not pay taxes or pay very little taxes. With the US pursuing these folks vigorously, they had to make a decision... Pay US taxes though they live somewhere else, or dismiss their US citizenship and reduce that tax burden.

Think of the accountants in Saudi Arabia, or oil workers, those the live in Canada, or that manage Ford factories in Mexico. Before, they may have gotten a small "perk" ie tax evasion for living and working abroad  but still retained their citizenship. Now the US is AFTER them for the CRIMINAL they are. (smirk) The mega rich, don't even have to think about it.. the lawyer will handle it either way. They can still hide their money.

So yes there probably is a rise in those "leaving" the US... but its because the laws changed making and marking them as high priority criminals.   I do not see a mass exodus of wealthy with their wealth leaving the impoverished masses to flounder in the debt we now find ourselves in.