A matter of overstepping?

I was listening to talk radio the other day since I am a glutton for punishment and there was some talk about something called "judicial activism." It seems that the phrase means different things to different people.

The President seems to believe that judicial activism means ruling a law unconstitutional. His law. His healthcare reform law: the Patient Protection and Affordable Care Act (PPACA). The talk show host disagreed. He felt that the Supreme Court's job is to decide the constitutionality of laws. I agree with that.  But it wasn't always their purpose.

Enter Marbury v. Madison (1803) [see here or here]. A brief synopsis:

The case began on March 2, 1801, when an obscure Federalist, William Marbury, was designated as a justice of the peace in the District of Columbia. Marbury and several others were appointed to government posts created by Congress in the last days of John Adams's presidency, but these last-minute appointments were never fully finalized. The disgruntled appointees invoked an act of Congress and sued for their jobs in the Supreme Court. (Justices William Cushing and Alfred Moore did not participate.)
Question

Is Marbury entitled to his appointment? Is his lawsuit the correct way to get it? And, is the Supreme Court the place for Marbury to get the relief he requests?
 
The ruling:
The justices held, through Marshall's forceful argument, that on the last issue the Constitution was "the fundamental and paramount law of the nation" and that "an act of the legislature repugnant to the constitution is void." In other words, when the Constitution--the nation's highest law--conflicts with an act of the legislature, that act is invalid. This case establishes the Supreme Court's power of judicial review.

It would seem, prior to this ruling, that the USSC did not have the power of judicial review.

Ironically, that ruling is also a prime example of judicial activism. 

At least, according to the talk show host who felt that judicial activism was the court assuming powers that it did not have. This was deemed "legislating from the bench."

There is no one alive who recalls what the Supreme Court did before this ruling. We have always lived in a system where the Court's primary purpose is to establish the constitutionality of a law.

I often wonder what it did before that.
 
But I am glad they do it now. It is the final check to the power of both Congress and the President.