(Sorry dupe - looked like my previous posts were lost. I refreshed several times here and did not see them.)
Color does not disrupt geometry. It does not mess with the overall UX. Rather it helps distinguish between applications, giving them a distinct, yet familiar look and feel. Also the new "colors of Windows 7" are very soft and easy on the eyes and the transition
between them is soft and easy.
I wonder more about Visio 14. It now has the Ribbon control, which is great, but does it have more streamlined diagrams and graphics. Visio 13 leaves something to be desired, to be honest - although it is possible to make smooth graphics with it.
Is Visio 14 using MIL or WPF. Is it using a new graphics engine or will it basically be the Ribbon plus some new diagrams and diagram extensions. That's really my main concern there.
A completely different question: Is "Quadrant" the basis for a new Visio? - Looks like there's some overlap there.