The United States Supreme Court has removed an obstacle to more widespread legal gambling. On May 14th the justices invalidated a federal law that prohibited states from legalizing sports betting. Here is the decision via Scotusblog.
Relevant Social Law Library resources include:
How to Play the Game: What Every Sports Attorney Needs to Know
http://encore.socialaw.com/iii/encore/record/C__Rb1145684
20th Annual Institute on the Gaming Law Minefield
http://encore.socialaw.com/iii/encore/record/C__Rb1142657
Gaming Law in a Nutshell
http://encore.socialaw.com/iii/encore/record/C__Rb1145752