Did suddenly all the techies buy in the "social" buzzword? I don't really think so: what infrastructural and, in general, technical challenges would Facebook be facing which aren't faced at Google too?
I tend to perceive Google as the technical innovator, bringing magic (1 gB email??? watching the world from above??? and free???) to the real world, whereas Facebook, despite it's cool API and Cassandra, is just vendor lock in.
But I digress: maybe the problem is that Google's already solved the problem leaving no space for new ideas?
Why would Facebook appeal more smart techies?
Most of the draw of Facebook is their 500mil users. I see popularity more than greatness. Google has and continues to do amazing things (unfortunately none of them in social).
Google moving into "social" is like a nerd learning to dance. With enough work they can do it. They'll be awkward at first. Facebook is hosting the dance because they have the biggest house. Facebook is good but mostly because it's the biggest. They don't offer many reasons for users or advertisers to be there other than "everyone else is". They can still become a lesser version of their current glory a la Myspace.
I guess the TL;DR is: You don't have to be at the doorstep of "war" to move in that direction. I guess Page sees it on the horizon and is moving to prepare now, instead of when it's upon them.