I haven't read the opinions so I don't know. What important parts of the act are you referring to?
Well,
Leon said he thought the defendants had established the constitutionality of: (1) restrictions on the use of soft money donations by national, state, and local parties to fund certain types of campaign communications (particularly candidate-advocacy "issue" advertisements) and (2) restrictions on the airing of corporate and union electioneering communications which promote, oppose, attack, or support specific candidates for office. I suspect we're going to find out these provisions were also upheld by the other judge in the majority.