In a way you are right, but I think this approach also provides them with leverage to hedge their bets.
The main differentiating factor in this case is their competitors are focused primarily on solving one problem, whereas Google is attempting to solve a multitude of problems in an attempt to win through convergence. That is to say, their solutions may not be as polished, but they are all in one place, presented to you in an accessible and convenient matter.
You may be proven right, it would certainly seem G+ has huge potential: everyone I know so far, and most of the reviews on the net are very positive. It will integrate into all the others google's products, and with that, google will be the king of social.
But that's not the point I tried to make. Based on the post, my opinion was that Google did not want to renew the deal with twitter (and vice versa) which is strange. They are at war already with everybody else (ms, apple, oracle, facebook) and don't need another enemy.
Microsoft uses this approach with MS Office and once things started going their way it was next to impossible for a competitor to attack any one product.
The main differentiating factor in this case is their competitors are focused primarily on solving one problem, whereas Google is attempting to solve a multitude of problems in an attempt to win through convergence. That is to say, their solutions may not be as polished, but they are all in one place, presented to you in an accessible and convenient matter.