No, only the "Lanscape LOD Texture Replacement" mod for now but I remember having a chat with a Finnish guy who told me there were lots more tweaks to Oblivion. Never got to check it out though.

will look into this, comparo with stock Oblivion vs Tweaked :D
oh yes, Rainbow Six Las Vegas 2 is a GPU killer too, at 1600x1200 max detail I get 18fps with 8800GTX:)