Someone at Hulu said that they may start charging a fee as early as next year for its online video services. People around the web are angry at the concept. No one seems to think Hulu can figure out a method to make people happy. I think that they can manage to hit hit a "freemium" middle ground. There is already a model for this – it's called television. You can get television for free broadcast over the air. Want more options? You'll pay for it.
Expect free video to still be on Hulu because otherwise online viewers will move to less legal alternatives.