Since we highlighted this growth yesterday we’ve spent some time discussing how this could happen. In addition to what Brett pointed out yesterday, it’s clear to me that there are a number of other reasons why Google+ is such a success:

The market now is substantially different to when MySpace, YouTube, Twitter and Facebook emerged. The internet is bigger, more connected and now, inherently social. It’s less of a challenge to add another new service as the familiarity of what social platforms can do and how they work is embedded in peoples psyche.

The internet in 2011 is far more global. From our data, it seems that only 10% of the Google+ userbase is in the US. This is unprecedented. Facebook conquered their home market before moving global. Google did in on day one. That’s why we think Paul Allen’s estimates are on the low side as it underestimates the international appeal. This is also underlined with a quick search in one of the first Google+ directories (Findpeopleonplus.com), where the top five cities run down as Dehli, New York, Mumbai, Bangalore and London.

For a majority of users, Google+ is a low engagement social network. It sits in the background, quietly linking up disparate content and services. Many people can participate and contribute on the service without even going there.

Google+ will be the social tool that engages the mass market. Facebook is still alien to many and Twitter will always be. Google+, with its integration with Google services, is a soft social platform.

Google+ focuses on many key drivers that appeal to the mass market; group video calling, privacy and simple sharing of personal content.

Google+ also seems to be getting a lot of influencer pick up with bloggers replacing all their platforms in one swoop with Google+. Only time will tell whether this will last.

Android integration and the non-stop rise of internet enabled platform phones will drive Google+ upwards. We recorded 229m android handsets across our 27 markets in November 2011, up by a frightening 70m from June 2011.

Integration with the Google homepage will inevitably generate sign ups. We benchmark Google as having an 85% monthly reach to over 1.13bn people. That’s just in 27 markets.

Ultimately, it looks like Google+ will become the biggest social network; whether it captures significant activity is the billion dollar question though. Currently, it looks like it will run in tandem with other players still growing. If Google dominates social to the detriment of other offerings, the social landscape will be a far less interesting place, but because the current environment is driving so much innovation, we don’t see that happening anytime soon.