Just from the autoblog pix, I'd have to say the "tweaks" are for the good. I will have to see it live for a better comment, but as a previous owner of an '07 GT/CS, I think this update has gone in the right direction. Subtle changes without changing the successful design of the past model, which did sell very well.
It appears the interior and dash area is much improved, and that is one area that needed work. Previously a lot of hard plastic and sharp lines; the new one seems to be "softened" a bit and looks better for it. The seats were not overly appealling in mine, and it looks like they are about the same in the new one. Mustang seats are not the most supportive, and I think Ford could do better in that area.
Overall, a good redesign. We'll see how it sells now in the age of Camaro/Challenger competition, and higher gas prices (coming back at some future date). Good work, Ford.