Digg has grown quite a bit over the years, as initial observers have seen. And if today’s mention of a $28.7 million funding infusion is any indication, the company is going to build itself some more. A whole lot more. It seems those repeat mentions by company founder Kevin Rose about a continued developmental focus in spite of sell-off rumors are going to become quite tangible very soon.

According to CEO Jay Adelson, Digg will work to accomplish three primary motions with the new investments (led by Highland Capital Partners): more infrastructure; the always-expected development of new features; and international expansion, with more hires to come. The last detail is the most important, for sure. The multinational push is scheduled to begin in early 2009.

Adelson of course describes this as “big news.” For a U.S.-based company with a claimed 30 million unique monthly users, nearly half of which reside beyond America’s borders, it’s rather hard to argue the opposite. Digg is not only up against the likes of Reddit (acquired by Condé Nast back in 2006) and Mixx and so forth, but also the very potent latecomer known as Yahoo Buzz. As a result, the focus on international growth in terms of local preferences and languages can only serve to help Digg maintain its distinction as a popular, powerful and user-friendly service across all parts of its membership and visitor pool and grow in kind.

Back on home turf, Digg will be shifting its current assets to a larger residence in San Francisco, and will be expanding in technical ability and in people power. The company is seeking additions to virtually the entire work crowd, from designers to developers to managers to sellers to engineers to QA folk. Which is really a sensible undertaking considering the business-wide boom that has just been triggered. No use idly sitting on the cash, especially when the multinational and multilingual push is to begin in several months’ time.

As has been said regularly before, if we’re to expect any changes to the Digg system, at least one eye should be fixed on the drive to broaden the engine’s focus more toward attracting casual users further into the fold, and more important still, for non-users to want to browse the service whatsoever. 30 million monthly uniques is substantial, but it presumably could grow much larger yet. $28.7m is quite a bit of fuel to drive Digg forward.

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