The Tax Cuts and Jobs Act is out, and you can wade through the 429 pages here. As this helpful summary of the plan states, it would eliminate the state and local tax deduction. If you pay high state income taxes–think California, New York, and many other places–you’ll care about this. Tens of millions of Americans claim this tax deduction, writing off their state and local taxes to reduce their federal income tax. Lots of taxpayers, Republicans and Democrats alike, could even rethink where they want to live. After all, it already hurts to pay high state taxes. No deduction is some serious lemon juice in that state tax paper cut.
https://www.forbes.com/sites/robertwood/2017/11/03/tax-bill-kills-state-tax-deduction-so-californias-13-3-prompts-more-exits/#28fa081e5463