I don't always post from third-party, alt.news sites because they're often the brainchild of poor journalism. This one echoes most of my concerns, and is reasonably well-researched, with citations that actually fit the context.
My general understanding is the Keystone will not improve our energy independence, creates relatively few jobs in relation to the overall costs of construction, and by the time the oil reaches refineries in the Gulf will actually use more power to refine than it supplies -- it's a net loss venture.
What it does promise is to make a handful of people very rich at the cost of taxpayers and the environment.