I agree, but behind changing colors and icons there's also the borders/shapes and overall layout of the UI.
The better interface is of course the one you can change, move panels, re-organize icons, change any of the UI colors etc..
But that's also more difficult to code it.

I dont find dark depressing, its been in all the pro applications for one thing, contrast for the eye.
This is just another exemple, Blender 2.5 mockups are dark and blue.


Of course MoI interface gonna change in time, and as I said if you need any icons (I do vectors ones) or mockups im there.
MoI need to be different vs other programs in term of UI, its already different. But sadly some people judge first by the UI.
And to be fair, I like the current UI and blue is not so terrible, but ive heard some people at my work asking me what I was doing in this program they never seen before. Just like if by the first sight it look non-pro, just like when sketchup started, some people sayed it was just a toy. This period of the web 2.0 and ugly flash website has made everyone aware of the design of things, people want apple because apple is "design".
But before the UI, the website need some work (for example the screenshots are old versions) the gallery could emphase more the work shown etc..
I know its ridiculous to try to make "pro" looking interface for programs that are poor, to make users buy them, to push more the interface to trick people into thinking its a great program when it actually lack of feature (the Delicious generation, glossy everywhere, 90% UI 10% features).

MoI is at the exact opposite, its really a great program that has an heavy potential and features, but lacks a little bit of ego :)
People that come in the MoI website must be saying "wow its so simple, I never thought nurbs where as simple as that"
Another website that I found is not at the same level as the program itself is Rhino website, but Rhino is far more into pro industry than MoI so a bad website doesn't matter because everyone know that Rhino is "a standard" in the industry.

MoI is not "a standard" in the industry yet but it will become one im sure, having a good UI and an attractive but still pro looking website are good points to the customer eyes. To start you should keep the current website look, but develop a bit more the "content" for example a features section, to make people see animations like the ones you put in the forum, that show every major features. Also put more informations about the MoI mesher because its an awesome "behind the scene" power of MoI. Making a good website is not about design, design is just the sugar on top, the apple website has a simple design but its awesomly build in term of layout, you have for all products complete informations and features with a lot of images/video and explanations.
Apple can take every little feature (for example the luminous keyboard) and make it a major one by using design tricks and words.

Im getting a little bit "off" the original topic there, I dont want to start a topic about Design so...
Keep the good work Michael, I dont know about the futur but im very sure that MoI is gonna become a major app into nurbs modelling soon :)