That's not journalism.
It is certainly not journalism. But offering up the information openly would have allowed journalists to take it and do what they wanted with it. I know this would open the door to crap journalists doing crap journalism, but the alternative - selecting a specific reporter or news outlet with views similar to Snowden's own - allowed Snowden to control the narrative.
Not just Snowden, either. That would apply to anyone in his shoes.
No he didn't. He gave the information to the Guardian, and they chose how to distribute it.
As I recall, he picked a specific reporter who initially rejected Snowden's offer. So I went and checked: Wikipedia is saying he initially approached Greenwald specifically before distributing his curated information to other outlets.