Google, still the reigning King of the Interwebs, has long faced pressure from Facebook to become more social. In a move towards that direction, they have added a feature called the “+1” feature.
The +1 button is shorthand for “this is pretty cool” or “you should check this out.”
Click +1 to publicly give something your stamp of approval. Your +1’s can help friends, contacts, and others on the web find the best stuff when they search.
This is a direct competitor with Facebook’s “Like” feature, that seeks to colonize the internet bit by bit.
How successful will Google be is anyone’s guess. My take on this is that Google might eventually win out, since it has the plus point of being literally all over the internet i.e it does not require content creators to agree to have the “+1” feature to be implemented, since it is in the search results.