Surprised? Not so much. Disasters like this are the logical result of passing a bill to see what's in it. Perhaps if the Democrats had been as interested in getting the legislation right as they were in jamming down the American people's collective throat, this wouldn't have happened.
Sure, some might argue that the "middle class Medicaid" flub was just a sneaky attempt to move more people into dependence on government. I don't deny that many in the Dem Party would welcome such a result, but given their performance on the economy and so much else, one has seriously to doubt that they have the competence to pull it off, except as a happy accident.