There is a lot of hysteria ITT about what the president and the senate should do, and I'm not sure why. It's really pretty simple. It is the president's right and duty under the Constitution to appoint a successor. He will. It is the senate's right to not confirm that successor. They won't. That is completely understandable given the importance of this position and the fact that we'll have an election for a new president and a new senate in less than a year.
Anyone feigning outrage about the senate not confirming Obama's pick is either a complete moron or just doing some political sniping.
Finally, Scalia was not a judicial activist just because you don't agree with his opinions. If you really think that, you don't understand what "judicial activism" means. It means reading something into the text of a law that isn't there, or just making law up, to reach a desired result. Scalia was the anti-activist. He would be the first Justice to say "this is an issue for the legislature - not the Court. The Constitution doesn't cover this."