The Bill comes into force today, 270 days from the day it was signed into law. There are three challenges/amendments to the UIGEA going through the US Congress which seek to either exclude or exempt games of skill from the bill or regulate online gaming.
The World Trade Organisation has also found the US guilty of breaking global trading agreements in a case brought by the government of Antigua & Barbuda - they are seeking over $3 billion per annum in compensation. Several other countries including Canada, Australia, Costa Rica, as well as the EU have joined in the claim for compensation.
Personally I think the bill will be amended to regulate the industry (and pay taxes to the US Treasury) but in the meantime the big sites will carry on as normal.