MOG, the very popular music portal and blog network, has closed a new $5 million funding round led by Menlo Ventures, with existing investors Simon Equity Partners and Scott Jones also participating. Menlo Ventures’ Sonja Hoel Perkins will join the company’s board as part of the deal. The company has raised a total of $12.5 million since it was founded in 2005.

MOG has been having a stellar year. In April the site launched a completely overhauled homepage, which now includes music news, reviews, a selection of top posts from its blogs, and a variety of other content. The MOG network now sees over 8 million unique visitors a month, with over 700 blogs that generate over 6,000 posts a week.

MOG’s existing products are obviously doing quite well, but I can’t help but wonder if the new round was in part helped by its unlaunched music streaming product, which we previewed back in January. At the time we called it Ultimate Streaming Music App that may never launch, because it only had two of the four major labels signed on. If MOG managed to get the remaining holdouts on board, the company would be a ripe target for investors. The company declined to comment on the matter, but we’ll be keeping an eye out for more on this.