In the gloom of the advertising downturn, consumer social networks expect income to reverse, while subscription-focused business publishers are holding their own. Somewhere in-between, business social network Xing is chugging along quite well - Q1 revenue rose 43 percent from last year to €10.76 million, its earnings showed Thursday.

That’s because the Hamburg-based, Euro-centric LinkedIn rival has an enviable 601,000 premium subscribers, each paying at least €4.95 a month. Xing may have added an advertising revenue stream late in 2007 but, with eight percent of its 7.49 million users choosing to pay, it’s little coincidence that company sales growth is lock-step in-line with that of its premium customer base. Next, the company will more tightly integrate Socialmedian, the social news filter startup it acquired in December, and is launching an apps platform to encourage outside input.

“Part one of social networking was building up contacts and networks,” Jason Goldberg, the Socialmedian CEO who moved from New York to be Xing’s chief product officer in March, told me. “Part two is, the network’s there - how do we get value from participating in these networks?”

Last week, Goldberg debuted the new apps suite with Xing News, essentially injecting Socialmedian in to Xing, and Xing Answers, a community Q&A feature. Together, they add Facebook-style activity streams to the otherwise stuffy world of business networking: “I might not have the time today to read WSJ.com - but when go to Xing I can see what stories my friends are reading. We’ve put the social graph filter on as a way to discover important information.” Away from the social, Xing also wants direct feeds from news publishers.

The new features operate on the OpenSocial apps platform, and Goldberg, who is getting by in Hamburg on only a smattering of German, says he’s working to instill more of a Silicon Valley ethos in the German company: “We’ve already adopted the Socialmedian shipping model, where we put out a new product every week, which is new for European companies, it’s more an American thing. One of the things I immediately did was to prioritise the OpenSocial framework; we’re going to be bringing on more than a dozen apps on in the next few weeks.”

But isn’t Xing just LinkedIn lite, and what’s the difference? For Goldberg, it’s a question of territory: “LinkedIn is a very successful American product - Xing is a very successful European product. Xing’s ambition is to be a European leader and to build that from there.” He said the premium model also differs from LinkedIn, comparing his starter price of £4.95 with the rival’s $24.95 a month. The idea now is to add to the basic networking functionality tools that further connect users.

Trying to corner the European market, Xing has built itself through acquisition in the last couple of years, buying Spain’s eConozco and Neurona before Turkey’s Cember for a combined €14 million. But Goldberg said future growth will be “organic”.

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