The devil is in the details and what they appear to be proposing is not exactly clear right now. I expect it might be by the end of the day or week, but . . . to me it currently looks like this:

Corporate income will be taxed at corporate rates. It's the taxation of the PASSIVE investment income that is affected. And  - it appears  - as if the proposal is to allow the first $50,000 of PASSIVE investment INCOME to be taxed at 10.5/10.0/9.0% rate. PASSIVE investment income above that is what is going to be hit.

Article also suggests existing PASSIVE assets are grandfathered. (What about income on the income generated by those assets?) How to segregate from NEW savings?

So you can still "save" all you want in your corporation. But growth on those 
(NEW?) savings above and beyond $50,000 annually will be taxed at punitive rates.