Since the changes to collective bargaining rights have no near term budget impact, it's been clear from the outset that Walker's aim in this whole effort is not budgetary but an effort to bust the public employees unions -- indeed, he's exempted the public employees unions, police and firefighters, that are more open to supporting Republicans. (Here's our report on Walker's late Friday press conference.) But this would seem to clarify any remaining question.
From talking to folks on the ground in the state and some very limited public opinion data (the situation in the country at large is less clear to me), my sense is that this is not wearing well for Walker.
In other news, state and national Tea Party groups are going to try to mobilize their own crowds today in Madison, with an assist from out of state folks like Breitbart, Missouri blogger Jim Hoft and VA based conservative operative training group American Majority.