I use praise a lot in my work with training collaborative groups so I enjoy sprinkling the "likes" around on social networks. It's not about giving people quantified validation, more like, "you are great, I see you, keep going, thanks very much, go team, hooray for us!"

I've been dwelling on that a bunch lately too. You're right @Greg K Nicholson, it's not the number of "likes" that matter, I'm more interested in who they're from. And really, the "who" changes depending on the subject matter. When I write a post about sexism that get's "liked" by one feminist I really respect, that counts for more than 10 "likes" from other acquaintances. Uh oh, my overengineering brain is knocking...