I stopped by Bayshore Station on Sunday to snap some photos of the current project. Although I can't source any official City documentation, the project appears to be a Transitway extension alongside the westbound lanes of the 417, then running underneath Richmond Road while working its way into Bayshore Station. The image below, based on a Google Map, illustrates the leg from the Richmond Road underpass towards Bayshore Station, where I took the photos:
As you can see, the roadway runs underneath Richmond Road and straight into Bayshore Station. Unfortunately the Google satellite image is quite outdated, and shows none of the construction, or the fact that the Richmond Road 417 on-ramp (the ramp joining the more vertical roadway, Richmond, to the more horizontal roadway, the 417) is now closed. Below are a few photos, and there are a few more on a Flickr album that is open for public viewing.
The view of the work from Richmond Road while driving over the 417.
Looking down the Transitway, through the Richmond Road underpass (standing roughly where the Richmond Road on-ramp used to be).