No, nothing can really be done to combat climate change at this point. We've breached the point of no return. We can slow it down, but we've done too much damage. This is a good start, but nothing is going to totally make things right again, short of going completely off grid.
The sad reality is that the majority of people turn a blind eye to issues such as this. The initiative might raise awareness but I doubt it will be enough to sway the public at large. It would appear that inconvenience trumps social awareness for most people. The general attitude of the North American population needs to change for this to be effective.
Although the governments love to shriek about climate change, they really don't have any good answers for combatting it. They just want more money and power so they can be seen to be doing something. In reality, none of the "solutions" proposed by the government even tough the scope of the problem. Bill Gates and his $1 billion, while a generous contribution, won't change that.
Will the venture make progress in combating climate change? Absolutely. It'd be pretty hard not to have a positive effect with a billion dollars of backing. But if success is equated with curbing climate change in the next few generations, success is essentially impossible barring a major shift in mindset by a whole lot of people in government and business. It'd take many more billions to make it worth changing for many of those people.