"In fairness to Shuttleworth, the near-universal switch to 16:9 displays is a bit of a game-changer. Anything that takes up vertical space on screen now must be considered very carefully."
My 16:9 monitor has just as much vertical space as my old 4:3 monitor had; more, actually, because 900 > 768. Vertical space is no more expensive now, it's just that horizontal space got a little cheaper.
Vertical space is generally infinite and horizontal space at a premium, or so people always told me when they criticized the way that I sacrificed 48px of the right side of my screen for an always-visible dock and gkrellm.
If vertical space is really important why not ignore client side decorations and simple use a WM (or WM theme) with decorations on one side, or both sides, of the window? A far more sane, simple and standard solution.