Apparently there's been some discussion at a high level for some time, but it appears things became more formal and concrete earlier this summer. Nothing close to final by the looks of it, certainly not as far as tying a train station into it.
http://www.660news.com/2015/06/26/de...-village-mall/
Here's a website with some broad statements about the redevelopment, which is supposedly being done by Ledcor for Primaris REIT. But Primaris was also bought by H&R REIT in 2013, so I don't know if that's changed, slowed, or accelerated plans.