Math has never been my strong suit, but I think I know just enough to put in perspective the Ontario government's effort to balance off the end of provincial sales tax exemptions with a cut to provincial income tax.
If you make $36,848 or more per year, the cut to the lowest income tax bracket (from 6.05% to 5.05%) will save you $368.48 per year.
That's the amount of sales tax you'd pay - assuming I haven't completely forgotten Grade 9 math - on $4,606 worth of goods.
So discounting the one-off cheques the government will be mailing out in 2010-11, if you're a mid-level income earner or higher, you'll come out ahead if you spend less than $4,606 annually on the goods that will no longer be exempted - coffee, gas, tobacco, newspapers, gym memberships, etc.
If you spend more than that amount, you'll come out behind - at least until any of the savings that businesses gain from harmonization are passed down to consumers, which will purportedly happen within a few years.
That's not to say this should be the sole or even the primary measure of harmonization; personally, I'm willing to pay a few extra cents for my coffee if it helps reverse the slide of my province's industry. But hopefully, it helps a little with understanding the impact on consumers.