In general, I think that the HST is more good than bad. It is much more efficient to have one tax instead of two, and GST is a more efficient tax than PST, in turns of the complexity of collecting and auditing it.
All GST that a business pays they get a credit for, whereas with PST, you only get credit for things you resell, things you consume, such as office supplies, you pay tax on. So they collect a little more money with PST, but at great cost in terms of waste.
It is true that switching to HST transfers some tax burden from business to consumers. In a perfectly efficient economy, that would all be immediately passed on to consumers in reduced prices. Realistically, it will only be partial. But businesses can't keep the money (or at least they can't enjoy it if they keep it), it gets paid out to owners as salary and dividends, and taxed at that level.
So to me, switching to HST is good overall, but if neccessary it should accompanied by tax rate changes in income taxes to make sure that the overall burden is distributed fairly, however that might be.