Google isn't being evil, they are being clever
"This is Google taking the big monopoly - search - and using it to directly promote their competitor to Facebook and twitter
...this is Google's 'Microsoft Moment' - this is the moment where they take their big monopoly and they say 'we're afraid of threats to the big monopoly, we're afraid of the next wave of services'
...it's a bully move" - Nilay Patel
First, consider why Google+ exists
I wrote a post back in November, 'Android - the critically important Google product'. I concluded this post stating that Google doesn't need Android for any other reason than ensuring there is a mobile platform upon which Google services can operate. An iOS and WP dominated world leaves a possibility that Google Search, Maps etc become irrelevant in the mobile space.
Isn't Google+ here for the same reason?
Luckily I don't need to say much here, Google already has.
"We are a bit surprised by Twitter's comments about Search plus Your World, because they chose not to renew their agreement with us last summer (http://goo.gl/chKwi), and since then we have observed their rel=nofollow instructions." - Google
Twitter was previously integrated within Google, twitter put a stop to that.
Facebook within Bing
Google+ is quite late to the social space, one has to consider why. Is it because Google is now a behemoth incapable of reacting in a timely manner? Google's reaction with products such as Android, YouTube & Gmail along with these products dominance prove that Google can still built products at the right time, also they are happy to purchase capability to 'get to market' as quickly as possible.
Consequently, it's safe to assume that Google's late entry to social is because Google wasn't originally planning to run a social network. I feel it's no coincidence that a year after Bing and Facebook announce their partnership Google+ was launched. Their hand was twisted.
Google+ is a fight to stay relevant
The consensus reached on the Vergecast was that Google needed to react with Google+, Facebook has the power to make Google irrelevant. However, it was argues that Google is going about it the wrong way. The Verge is wrong, this is the only way of doing it. I don't believe Google needs to beat Facebook, just become big enough that it starts to create a more open social internet.
Google gave Facebook and twitter their chance. Facebook and twitter both decided to do their own thing, forcing Google to create Google+. Twitter can't have it both ways - they either integrate with Google or don't - you can't argue one way or another, Facebook has been quiet as they signed with Bing already.
Google is being bullied by social networks that are scared to open up, not the other way around.