So in other words its still cheap not as cheap as it used to be but considering that the US uses the definition of Worldwide income for taxation purposes it saves people who have good passports from needing to pay more taxes to the US government a significant cost savings.
When the Citizens and the Corporations want to leave somethings up
http://www.telegraph.co.uk/finance/economics/11065125/US-taxes-are-far-too-high-no-wonder-companies-are-fleeing.html A study by German economists ranked the United States 94 out of 100 nations for overall “business tax attractiveness”, behind countries such as Pakistan, Greece, Russia and Nigeria.
Given these bad policies – a high tax rate and a worldwide tax system – imagine you are a major investor in, or senior manager of, an American-domiciled company that competes in global markets. If you can somehow take your corporate charter (and thus your legal HQ) out of a filing cabinet in the United States (most likely in Delaware) and shift it to a filing cabinet in a nation with better tax policy, that one step can substantially benefit shareholders, with secondary benefits for employees and customers. Hence that’s why US firms are buying foreign ones and then relocating themselves abroad. It’s important, however, to understand that there are limits to what an inversion can achieve.
No matter where a company redomiciles, for instance, that doesn’t change the fact that it will still owe tax to the IRS on US-sourced income. But
no longer having to pay tax on non-US-sourced income is more than enough reason to consider a new home. 
