I have business there and of the dozen or so states we operate in it is the most punishing tax regime. They have both a standard income tax and this crazy thing called a personal property replacement tax, plus they use single factor apportionment which is very costly to multi-state companies without significant real-estate or payroll in the state because you end up paying state tax twice on the same income to both IL and the 3 factor states where you do have employees and real estate.Funny - but he ran on a platform for a constitutional change to instituting a graduated tax in Illinois.
Pretty ethical guy, but Illinois is headed for a 10% marginal personal rate. We are going to tax snow to pay the State's bills.
That said, it's punishing because I earn a significant amount of income there. So better off paying lots of tax to IL where I earn lots of income than no tax to Mississippi or Kansas where we can't earn a cent. I kind of feel the same way about CA. You pay a lot of tax but there is also a ton of opportunity there. I feel more sorry for Kansas where the "Kansas Experiment" showed that simply having lower taxes does not create opportunity.
. Personally I'd love to pay a top marginal rate of 70% on earned income over 10 million. I say bring it on.