Ever notice how some people are a little, ah, delusional? For example, some folks were telling me recently how Google's social network Google+ usage was going down and the site really wasn't that popular. Seriously. Clearly these people have been under a rock, or perhaps too besotted with Facebook, to notice that since Google+ opened its doors to everyone, its growth has been nothing short of explosive. Indeed, Google+ made it to 50-million users faster than any other social network.

According to Paul Allen, founder of Ancestry.com, a leading genealogy site and Google+ unofficial statistician, “Google+ likely crossed the 50 million user mark. And since being opened to the general public (over age 18) last week, Google+ has been growing by at least 4% per day, meaning that around 2 million new users have been signing up each day.”

To be exact, it took Google+ 88 days to hit 50-million users. MySpace—remember them?--took 1,046 days. Facebook, with 1,096 days, took even longer.

Allen now finds it hard “to imagine a scenario where Google+ doesn't end up with hundreds of millions of users. It's just a matter of time.” I agree.

Besides liking Google+ for its own virtues, Allen points out that “By integrating +1 and Circles (targeted sharing) and other Google+ functionality into its Chrome browser, Android phones (and tablets), Gmail, Google Reader, Blogger, Google Photos, and other properties, Google+ will give its more than one billion users repeated chances to sign up for and use the functionality of Google+.”

It also doesn't hurt Google+ any that Facebook can't seem to stop tinkering with its interface and has less and less respect for its users' privacy . Facebook is unquestionably the social network leader, but between Google+'s explosive growth and its own mis-steps, it may yet lose its throne.

This isn't just Allen analysis by the way that shows Google+ experiencing explosive growth. According to Heather Dougherty, Director of Research at Hitwise, “Google+ emerged as the third largest site in the Social Network and Forums category last Wednesday, a day after the site went from “invitation-only” to "open access" available to everyone.”

Hitwise's research showed “a massive spike in market share of visits for the site, with a 1269% growth from the week ending September 17th to the week of September 24th.” Thus, “In just one week, Google+ went from ranking as 54th most visited site in our Social Networking and Forums category to 8th place.”

If I were Mark Zuckerberg, I'd be worried. Very worried.

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