Google's social networking site Google+ could become a key tool for charities: the search engine recently rolled out new features in the US that may make charities rethink their approach to social networking. The UK is next on Google's plan.

Google+ – which opened its +Pages for brands in November appears to have attracted a significant number of charities. Mimi Kravetz, senior project marketing manager at Google, said take up among UK charities had "exceeded early expectations". The service itself, she said, has grown quickly, with 40 million users within 100 days after its launch in summer.

However, until the announcements, consensus among charities appeared to be that there was little benefit in paying attention. Most charities appeared to be pushing similar content on Google+ to their Facebook and Twitter feeds. The British Heart Foundation's community and social media manager, Robert Kusabbi, described Google+ as "social for the sake of social". He pointed out technical drawbacks, such as a lack of information for administrators on followers.

But Google's new personalised search feature, which it has called "Search plus Your World", means account holders – anyone signed in to Google via features such as GoogleMail or GoogleDocs – will see people and organisations they are connected to on Google+ prominently in their search results – just beneath the search box. And that, say some experts, could prove the tipping point for Google+ becoming just as significant for brands, including charities, as Twitter and Facebook.

So attracting followers on Google+ could become a priority, and Google has created web pages to help charities understand what they can do on the site. But which charities are on there, and what are they gaining by putting time and effort into their presence on the site?

Debt charity the Consumer Credit Counselling Service (CCCS) is in the middle of a three-month experiment with Google+ to improve search-engine optimisation (how high its content appears in Google search results) for its consumer guides.

"Our aim is to appear higher up rankings and to compare how we did in 2011 with 2012," says Peer Lawther, social media manager. "We're including keywords in Google+ posts in key areas where we've got debt help guides.

"All we can do is experiment because Google won't tell us how it works, but it has to help because it is, after all, Google. We're curating Google+ once or twice a day to see if there's traction. And these new features can only help us."

Cancer Research UK has found its Google+ feed has attracted a clued-up crowd of early adopters keen to discuss the charity's medical science content. When the charity launched a report on lifestyle and cancer in December 2011, it attracted 319 "shares" on the site and a lively, focused discussion.

"We made a strategic decision to have a play with Google+," says Steve Palmer, head of the charity's science press team. "We're pushing more science content than on Twitter and Facebook – Facebook is good for fundraising. On Google+ we tested and found our science information was attracting a lot of interest."

Tearfund uses Google+ as an internal communications tool: "We've explored the 'hangouts' feature to talk to staff working from home, though not overseas yet because of technical problems in Africa," says Nick Harris, digital marketing manager. "We do hangouts with campaigners and senior volunteers for briefings about upcoming campaigns. It's like a small webinar [web seminar] where we can talk to six or so people at a time."

London-based charity Zakat House is on Google+ but Mohammad Shakir, communications coordinator, says while the site is potentially useful because it's integrated with Gmail and Android, the organisation has not put much effort. "Decision makers and influencers are not yet on Google+ - they're on Twitter," he says.

There are signs, however, that that could change soon. David Cameron, Nick Clegg and Ed Miliband are all on Google+. The content is patchy but commercial brands are taking its potential seriously: Cadbury recently chose Google+ to launch a new product.

Whether take-up will reach Twitter and Facebook levels remains to be seen, but as CCCS's Lawther points out, Google is a company with the resources that will make the service hard for charities to ignore.

"In time, I predict it could become as big as Twitter," he says.

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