It's been less than a week since Google+ cast off its invite-only shackles and announced it was opening its doors to everybody. But then Facebook went and shifted the goal posts.
About a week ago Vic Gundotra, Google's Senior Vice President of Engineering, posted an update on the official Google Blog, highlighting
a number of incremental new features for users of the 90-day-old Google+ social network. The piece de resistance (and so-called 100th 'feature') for the fledgling platform? No invitation required. Google+ was now open to everyone willing to sign up, having successfully graduated from a self-imposed limited-user "field trial" status to a considerably more free-for-all beta.
It was a decisive step forward for the much-publicised Facebook competitor, and it almost immediately saw impressive uptake results on the ground. As noted by
Search Engine Land, unofficial Google+ statistician Paul Allen
recorded a striking 30% growth in Google+'s user base after just two days of the open-door policy taking effect, boosting the platform to an estimated 43.4 million users, with an influx of more than 10 million since the invite-only restriction was eased.

Facebook's new-look profiles are set to reveal ever-more activity-related user information.
Pretty huge stuff. But in the same week (timing which may well have prompted Google's hand), Facebook held its annual f8 developer conference. Last year, the event saw the introduction of, among other things, the Facebook Like button -- a mechanism which has since effectively overrun the internet as we know it -- so anticipation for game-changing social innovations this year was high.
And Facebook didn't disappoint,
unveiling Timeline (a comprehensive update to user profiles to be rolled out in a few weeks, with a greater focus on visuals and broad user-based historical context) and, perhaps most significantly, expanding upon a new range of "social app[s]" that run in Facebook and are tied to media the user engages with.
Effectively, if a Facebook user listens to a song from within Facebook with the new Spotify tie-in (announced last week at f8) for example, they'll be instantly publicising the fact to their friends. Ditto for videos watched in video players accessed from within the site, and also for news articles read in Facebook (using publishers' media apps, essentially mini web sites for established media brands who choose to partner with the social network). Increasingly, Facebook is becoming a bigger, ever noisier corner of the internet (and less of a welcome place for the shy, retiring type).
It seems the introduction of Timeline alongside the adoption of the new range of social apps will bring a huge transformation in the look and feel of the world's largest social network (and one which almost overnight will distance it from the already more conventional-looking Google+), but the enhancements are bound to court their share of controversy and incur the wrath of change-resistant (and weary) end users.
After all, not only are end users faced with an abrupt new sharing paradigm (which looks to broadcast pretty much everything they do) but increasingly Facebook is self-consciously shuttering its own users in, pressuring them to spend less of their free time on the net at large and more time within its own hermetically sealed social biosphere. As
one commentator put it: "It’s breathtaking. And since it is all done with hard links to a single proprietary hub, it is eating the web like a cancer."
In light of the outrage users have expressed in the past fortnight with regard to relatively mild cosmetic updates to the site's newsfeed feature, the next month is likely to present a difficult learning curve for many of the 750 million active Facebook faithful. Google+ will certainly be hoping so, waiting in the wings eagerly to catch any deserters.