While I realize it mentioned it in the article, and that it's forthcoming, I'll withhold my opinion of the "threat" to Twitter and Facebook until I see what kind of API they're going to roll out for Google+.
One of the reasons I like the older services is that I can access them via SMS - in fact, Twitter is just about perfect for that use case.
One of the reasons I like the older services is that I can access them via SMS - in fact, Twitter is just about perfect for that use case.