I think most of the gifts of land and real estate would be incremental to what the donor would normally be giving. If the donor's current capacity to give is his or her ability to donate cash, and they own a significant asset in the form of real estate, which has a low cost base, they're just going to hold onto that real estate. However, if you remove that tax barrier to giving, then they do have the capacity to make a much more significant gift.
Under the Canadian Income Tax Act, the real estate would not actually have to be transferred to the recipient charity. The individual could sell the real estate and donate the cash proceeds, or a portion of the cash proceeds, to a charity within 30 days and still be exempt from capital gains tax.