Would you believe Twitter could pull in $140 million by the end of next year? Twitter’s executives think so, according to one report. But where will that money come from? In a world where MySpace can be king of the hill one year and shedding jobs the next, how does a company build a plan that lasts? Should companies charge corporate users? Rely on ads? So much to think about. And so far, no one’s got any answers. Of course, just because Twitter has figured out how to turn a profit, doesn’t mean you can’t use Twitter to give your business a boost. Check out these links for social media marketing strategies and sign up the SmartBrief on Social Media daily newsletter for even more goodness.