When it is ready, is that a good answer? Naw, not what you want to hear but they need to work some stuff out and when they are ready they will release it is and seems to be all indications. I would prefer it to be in good shape before releasing it, in the mean time you can still go on Tribble.
Ignore anyone thats says "when its ready" because not only is that obvious, its also not what your asking. The ACTUAL answer to your question is that it is scheduled to go live around the same time the current featured series ends(3/5). Dan said so in the engineering report he posted yesterday. That may change, but that is the plan ATM.
Also, just FYI, Season 3 lasts until Season 4. So the Foundry will be going live in Season 3.