And then what did people think when - wait for it - the third website came along. Or the fourth... or the billionth!?
It turns out that there was room on the web for lots of websites, and I suspect that it will be equally so for websites that have features which enable social interactions.
So why are people getting so excited that Google have added features which enable social interactions to their arsenal? I believe that it would be less likely that large companies wouldn't be making investments in social (or mobile, or cloud).
People love taking the "this or that" approach when talking about websites. Even more so when companies such as IBM, Microsoft, Google, and now Facebook and Twitter are involved.
I fully expect that even companies who have lagged in leading edge social upgrades - such as Microsoft - will surely venture further into this space. And so too will others. There's plenty of room.
I hear the argument made that, when a new social site comes on board that "Aargh, it's another social site that I have to check". I think that's just a matter of perception and largely depends on what you are on the social network to do.
For me, I'm happy to keep my Facebook account if it allows me to communicate easily with the peer group that I am connected to there. I'm happy to use LinkedIn to communicate ideas that are linked to my business groups, and I'm also happy to use Google, Microsoft, and any others to communicate with whatever groups form there too. After all, at the end of the day, it's just another mobile app that I need to install, and there's no cost to me in doing that.
People need to face up to the fact that social is the new way that we connect and share ideas and information. Who would honestly believe (or want) that this would all happen through a single provider.
Certainly not me.