I read somewhere that the idea for a pink Bold was tossed around, but later scrapped because the type of people that buy the Bold are pretty much high-end business users (because it's so damn expensive). Whereas something like the Pearl has a wider user-base. There really wouldn't be much of a market for it. But who knows, when the price goes down we may see something different.

If you really wanted to have a Bold in a different color check out http://www.colorwarepc.com/

It's a bit expensive but if you truly wanted a fresh and unique device that's where to go.