I love that people still try to argue that Google and Facebook aren’t at war. They’re absolutely at war. And I predict it will quickly get much more ugly than the Google/Apple war.
Apple doesn’t have an easy way to threaten Google’s core business. I guess if they go with Bing across all their products by default that could hurt, but that’s not an Apple product. (Plus, I think the reason they haven’t done that yet is because they simply believe Google is better at search — Apple won’t make a call that hurts their product.) You’d think Android threatens Apple’s core business, but that’s not really happening (see: Apple’s results quarter after quarter).
But Facebook and Google could easily threaten each other’s core businesses. Google has already started going after Facebook with Google+. Expect Facebook to go more seriously after search — and more importantly, contextual advertising across the web — probably with some help from Microsoft.