Open Social is launching tomorrow, and it’s being announced all over the web and via twitter.

In a nutshell, Open Social is an open web API that can be supported by two kinds of developers:

“Containers” — social networking systems like Ning, Orkut, LinkedIn, Hi5, and Friendster, and…
“Apps” — applications that want to be embedded within containers — for example, the kinds of applications built by iLike, Flixster, Rockyou, and Slide.

Open Social is very similar to the Facebook Platform announced a few months back, however, Open Social is a standard that can work across all adopting services.

My favorite part:

Open Social — by making this exact same kind of opportunity available to any other social network or container and every app developer and site on the web, in an open and compatible way — will prevent Facebook from having any kind of long-term proprietary developer lock-in. Developers will easily write to both Facebook and Open Social, and have every reason to do so — in fact, 100+ million reasons to do so.

When proprietary standards are threatened, I am a very happy guy.

Reference.