It's .57% of gross receipts, with the first $1M exempted, and a deduction from the gross receipts for either labor or purchases... I believe that was set at 35%? And I don't recall if it was materials purchases or capital equipment...
So in the example above, $2M in receipts/yr on $1.9M in expenses (let's assume it's $1M in labor and $900K in purchases/capital, so the labor is higher and is what gets deducted) the total liability would be $3,705.00. (($2M-$1M)-($1M*.35))*.0057=$3,705.00.
Supposedly there are a few other exemptions and deductions for specific things, too. I haven't gone through it in detail.
I'm certainly not in favor of this tax, don't get me wrong. It's a money-grab for the already-bloated general fund, and little (if any) will actually go to education, and I don't even think education spending is in a "crisis" or whatever they want to call it. But that said, mark my words, few businesses are going to close up or leave the state over this. You'd have to be a pretty high-margin small business to really get hurt by this; conversely, if you're low-margin, you probably don't have the funds to up and leave, and you'll stick it out by trimming costs somewhere else. Some of the cost will get passed on to customers, but that's a bit of a game too because the tax is on gross receipts, not profit. So if you raise prices, you're basically just raising your own liability.
This is essentially aimed at medium and large businesses that can afford to cough up the money, but are too big or entrenched to seriously entertain leaving, and that's totally by design.
I work at a family-owned business that WILL be heavily impacted by this, and lobbied very hard against it. It sucks, but we're not going anywhere... it's certainly been considered. The fact that Oregon doesn't have a sales tax still figures in positively, for now.
I've got to give the Republicans props on this... they gave it their best shot, and managed to (mostly) can the shitty gun bill in the process. Oregon Republicans finally showed something resembling a backbone. I don't think it will be enough in the long term, but oh well...