The lifetime carry bill was also signed into law. They were signed about the same time, I think.
Check out:
http://www.in.gov/legislative/bills/.../HE1176.1.html to see what the bill does.
The "backdoor registration" section replaces the form that went to the ISP already with the 4473. Not ideal, but not as big of a change as some are making it out to be.
As to "Castle Doctrine" ...
As I read it, the law simply extends existing protections. In some situations it applies to duty to retreat outside the home, but it
is specifically "castle doctrine" as well.