2. Roberts has a deep and wide judicially conservative record. He cannot be called "liberal" in the context of American politics; it's not even up for debate. The man and his judicial practice is as conservative as they come.
3. I really don't see why it matters. The justices' political leanings have nothing to do with whether or not their decisions are "correct" or not (although it may provide insight into why they decide one way or another).
[0]www.heritage.org
In a nutshell, the dissent would have also ruled against Aerio, just for a different reason than the majority. This sentence from Scalia's dissent should put things in perspective:
"I share the Court's evident feeling that what Aereo is doing (or enabling to be done) to the Networks' copyrighted programming ought not to be allowed."