Amazon.co.uk and Zavvi.com are listing the Shada BR as Region-Free. blu-ray.com is listing it as Region-B though.
Someone (American) involved in the production said they expect that it will be region free. Also, the Blu-rays for Spearhead from Space, the TV Movie (useless upscale), and Power of the Daleks were region free.
But yes, it’s true that you won’t know for certain until people can actually check for themselves. I don’t have a region free player, but I do have a blu-ray burner. In the rare case that I end up with a region locked disc (a surprise, or the only version available), I just burn it without the region restriction. Obviously not everyone can or wants to do that.