"I guess to call them the social network of the past is an exaggeration considering they still have, what is it now, 1 billion users," he said. "I think Google's just trying to legitimize itself as the better alternative to Facebook. I think Facebook has taken somewhat of a publicity hit based on the botched IPO, so kick them while they're still getting up."
Kerravala said he expects the assault to continue.
Horowitz said he couldn't release the latest user numbers for Google+ but pointed to a report released in September that said the site has 100 million active monthly users. It's a big number until it's compared with Facebook's reported 1 billion active users.
Undaunted, Horowitz said the social network is moving in the right direction and has the benefit of being late to the party and seeing what works and what doesn't.
"It's a question of time frame. In five to 10 years, absolutely we aspire to be a place where you have an uncluttered, meaningful connection...," he added. "It's never fun to be late to a market, but it does afford you an opportunity to talk to users. What needs are not being met? What do they like and not like? We believe in the online world you should be able to have a conversation with your cycling buddies that stays with your cycling buddies."
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