Regardless of how I feel about Go as a language... I don't trust Google to perform well as the steward. It may be open source, but that means nothing if people stop working on it.
If it doesn't become popular, I think they will just let it die. If they start trying to make it popular, I think there will be a big push back from the great unwashed masses of people who want obvious features and then it will die. Only time will tell.