I am sure HTC never intended it, but the happy hackers over at XDA-Developers have been hard at work at letting uses customize their Diamonds. If you don’t like the look the carrier gave your phone, you can now pick and chose amongst the many themes available. All you need is Diamond TF3D Config and the themes found in this thread.
Avid tweakers would be happy to know that the same hackers are hard at work creating further ways to customize TouchFlo3D, including the ability to add their own tabs to the interface. I can hardly wait.