Reddit, the headline aggregator and discussion site run by the parent company of Wired magazine, features plenty of talked-about stories. But only recently has it seen news that bodes well for the site’s own business.

Rival Digg‘s botched attempt at a redesign and the announcement of a Reddit-inspired rally in Washington D.C. by TV personalities Stephen Colbert and Jon Stewart have bumped up the site’s numbers. Now the site has announced that the buzz has brought a new ad campaign from a very big client — Microsoft.

Reddit’s raucous online community may not seem like the friendliest environment for advertisers like Microsoft. Ads from big companies have appeared before on Reddit, usually in the form of broader campaigns for Cisco, Amazon.com and others sold by Condé Nast, the publishing giant that owns Reddit.

But the more lucrative campaigns specifically tailored to a site’s audience have been rare for large companies, as they require a deeper understanding of the site. Neither Microsoft or Reddit disclosed the value of the ad deal, which will center around the upcoming release of Internet Explorer 9 browser.

“Microsoft is getting ready to release IE9, and they reached out to us because they genuinely want to start a dialog with the Reddit community,” wrote “KeyserSosa,” the moniker of a Reddit moderator, in a post on the site. “In fact, they’ve taken the unprecedented step of putting the Reddit team in charge of this entire campaign. This is a great deal of trust for an advertiser to offer, and we should both take it as a huge compliment.”

So what does this special campaign offer for Microsoft? A very hands-on experience with the community on a site whose users spend a relatively high amount of time on it, compared to its competitors. The announcement of the ad deal itself drew over 1,700 comments.

“Users are being encouraged to download IE9. Developers and some people from the Microsoft team will be responding to technical questions, criticism, and reports of bugs,” said community manager Erik Martin. “On Reddit we allow users to comment on ads so they will be giving direct feedback. We also have a section called ‘IAMA,’ in which people with certain occupations tell the community about what their jobs are like. The people from Microsoft will be doing this too.”

I’ve reported in the past about a similar campaign run by Reddit for Electronic Arts that helped to build buzz for that company’s “Dragon Age” games. In that campaign, a whole new section of Reddit was started for fans of the game. The company was said to be pleased with how a community developed around the game. That community was still there when the sequel came out long after.

Martin said the Microsoft deal is “encouraging” because it shows Digg’s redesign and the Colbert rally announcement are changing the public’s perception of Reddit — or, more likely, making them aware it exists at all.

“I think it showcases this increased awareness of Reddit, that potential advertisers and brands want to take part in our community,” Martin said. “Just because someone has a million followers or a site has a million views, they don’t necessarily have the power to influence culture and start movements or get people excited. This makes advertisers feel positive about having us because we are involved in an event like [the Colbert rally] in which we are a part of the story to some extent.”

Having said that, numbers do matter. Unique visitor numbers at Reddit are on pace to jump more than 1.5 million from August to about 9 million this month, according to the site’s internal statistics. Competitor Digg does not release internal numbers.

Martin says he’s not sure if the boost occurred because of the Digg contretemps or the mainstream exposure on Colbert’s popular Comedy Central news-satire show: “Our traffic has certainly gone up in the last few weeks but it’s hard to say if that is because of the Digg fallout or Colbert. There’s been an lot happening. We have seen an increase in people seeking advertising overall.”

The challenge for Reddit now: Getting those new users to exhibit the same kind of loyalty Reddit’s core audience has shown — and keeping the ad dollars coming.