Twitter to close to finishing a round of funding which would value the social-network micro-blogging site at $1 billion, according to the industry site TechCrunch. In February, an earlier funding round led by Benchmark capital valued the company at $250 million. Despite its rising popularity, the site, where people post 140-character messages, has struggled to figure out a way to become a viable business. The site reached 44.5 million visitors in June, 15 times more than it reached a year prior.
