You will have to wait until actual proposals are published, which will probably be in next week's budget.
But my understanding is that buy to let landlords are first in line to be hit with the extra tax, because it is them who have (until the credit crunch at least) made very large profits out of thin air, on the back of the rising housing market. And to a certain extent, it is buy to let landlords who have created the rising housing market by tying up properties, thus reducing supply and driving the price up for "normal" buyers.
As far as I am aware, the main exceptions, if there are any, will be for entrepreneurs who start businesses which become successful. They will not be stung for gains that are down to their own hard work growing the business.
If the Government presses ahead with raising capital gains tax in line with income tax, investors would see the tax they pay on their profits rise from 18 per cent to 40 or even 50 per cent.This could be from immediate effect of from the new tax year.