Employees at MSNBC.com are buzzing about March’s Nielsen/NetRatings. The numbers, which came out this afternoon, show MSNBC.com beating CNN.com and Yahoo in the online news race. MSNBC.com delivered almost 25 million unique users last month: 24,847,000, to be precise. Those are individuals, who probably clicked through more than one page. Yahoo had 23,434,000 and CNN.com had 21,911,000. It’s just one month, but it’s a good sign for the site, which has seen its streaming video become wildly popular…