I watched a cosmology lecture given by Leonard Susskind that convinced me to put my money on dark energy being a pressure caused by energy that is evenly distributed throughout the "vacuum" of space. However, quantum physics predicts that there should be a much larger energy density (i.e. many magnitudes larger). Have there been any more recent findings or theories that could shed light on this discrepancy?
There are roughly two possibilities: either there isn't a large vacuum energy, this would imply that there is something missing from quantum field theory. We don't know what it could be.
Or the zero point energy really is as large as QFT predicts, but there is something else that prevents it from having a large cosmological effect. We have no idea what that could be.
We might get more of an idea if we find out what Dark Matter consists of, or a good quantum theory of gravity we might know more.