As preparations for the upcoming G20 summit kick into high gear on Toronto's streets, people are taking to social networking sites to pass along information about the event or to complain about the traffic headaches it's causing.

Toronto police have launched a social media hub where Internet users can learn about the security measures being implemented for the international meeting, which will take place in the city's financial district on June 26-27.

The hub directs users to five different Twitter feeds, three Facebook pages and a long list of YouTube videos.

The "payoff" of using such channels "will be an educated and informed public, who will understand the security measures and the affects on those living in and around the summit security zones," Toronto police spokesperson Meaghan Gray said in a statement posted online.

Those intending to hold demonstrations are also ramping up their social-media presence. The Toronto Community Mobilization Network, which is helping to coordinate protest groups, is posting videos online along with frequent Twitter messages.

In one recent Tweet the group asked Toronto police and the G20 Integrated Security Unit to "stop sending cops to marches, demonstrations, meetings and our community spaces. Especially undercover ones."

Likewise, non-governmental organizations such as Oxfam Canada are posting details about demonstrations and other events they're planning around the summit.

As Sidneyeve Matrix, a media professor at Queens University puts it, "organizers are using social media for its real-time capabilities -- they're pushing out information."

But everyday Torontonians are also weighing in, usually to complain about how the summit is changing the city (in some cases, by posting photos of G20-inspired graffiti).

"Wow I had no idea downtown Toronto had the Berlin Wall running down the centre of it," Tweeted Scott Duffy, referring to the barrier being erected around the Metro Toronto Convention Centre, where the summit will be held. "Thanks G20!"

Matrix, who has been studying how social media are being used around both the G20 and the G8 summits, said there has been plenty of downbeat sentiment swirling online about the events.

"There's a lot of pushback, a lot of resistance, a lot of negative opinion right now," she told CTV.ca.

"I don't think it's changing the event but I definitely think it's shaping public perception," she added. "They say that people don't really believe advertising, we believe our friends -- I think there's a power there."