I decided to take a chance on wrecking my beautiful Trusty installation, and move from the 331 to 334 video drivers. I’m sure 334 will eventually land in the Trusty beta, but I love playing on the bleeding edge.
Rather than install them manually, I figured it would be much easier to jump back to the official 334 driver packages if I used one of the PPAs I could easily purge. Edgers doesn’t have the 334 packages yet, so I took another chance on a different PPA created by Joseph Yasi (https://launchpad.net/~joe-yasi/+archive/xorg-related).
I was pleasantly surprised to find that there were no issues at all, even with Bumblebee and Primus! Everything’s working great with the stock 3.13.0-17 kernel.