Here's a comparison chart between the three editions:
http://gopro.com/product-comparison-hero3-cameras
I think if I'm going to get a 3, I want it to be more equipped than the 2, that's why I'm going to get the Silver Edition. It's kind of nice having the flexibility to choose what level of product you want without getting a whole bunch of extra features that you'll never need.
The only thing the White Edition gives you over the 2 is the built-in wi-fi, I think.
Which to some may be worth it