Sure, the revelations of NSA overreach are important.
But I think the Snowden story is important as well, perhaps even more important. It's not really about Snowden, personally. It's about the power and secrecy of the government. It's about individual conscience and defiance. It's about how we, as a society, deal with non-conformity.
Compare Snowden with Bradley Manning. Compare Manning with previous whistleblowers like Daniel Ellsberg, Mark Fein or Thomas Drake. Manning's leaks were much more consequential than those that came before him, but things turned out pretty badly for Manning himself. Snowden clearly thought about how to increase the impact of the information he released, as well as how to decrease the negative consequences for himself. The next leaker, whoever it turns out to be, will undoubtedly learn from Snowden's example, just as Snowden learned from Manning.
Snowden's story is important for the rest of us as well. Most of us will never have the chance to do what Snowden did. But we all face situations where doing the right thing could lead to negative consequences. Seeing what happens to Snowden, seeing how we collectively react to what he did, in the media and in person, who can avoid putting himself in Snoweden's shoes? Who can help asking, "What would my family say about me if I did something like that?"
I think the focus on Snowden's story can help us figure out what kind of society we want to have, as 911 recedes into the past. Ultimately that's more important than the news that the NSA, the government's largest spy organization, is actually spying.