As a member of the Senate Intelligence Committee, Wyden had been briefed on the top-secret-plus programs that we now all know about. That is, he knew that he was putting Clapper in a box; He knew that the true answer to his question was “Yes,” but he also knew that Clapper would have a hard time saying so without making headlines.[0]

That makes it sound like Wyden was attempting to force Clapper to release classified material so he wouldn't have to. Interesting that Wyden, despite knowing that Clapper's statement was false and aware of the program, chose not to dispute Clapper's statement, or release classified details of the program himself.

0. http://www.slate.com/articles/news_and_politics/war_stories/...

This is exactly it. Wyden purposely put him in an impossible situation so he could hang him with it later. If Clapper has done his job well in other respects then this incident is irrelevant.

Lying to Congress is still a crime. He could have legally declined to comment, but not lied.

Declining to answer is a sure giveaway of the answer in an open hearing ;) I suspect there's a number of situations where lying to Congress is not a crime. The "Gang of 8" and the "Gang of 4" are almost always aware of the truth, usually the entire intelligence committees. Members of Congress are not automatically trusted with the deepest national secrets just because they are elected.