A quick google shows both round and rectangular, but the renders in the most recent material mostly appear to show round pillars, but with larger non-circular structures at the crossing points.^ Cool to see the pillars will have a curved shape as they meet the guideway. Although I can't remember if they'll all be like that.
Davenport Diamond Guideway project sees extended hours – What’s behind the work and effort to keep the noise downDavenport Diamond Guideway project sees extended hours – What’s behind the work and effort to keep the noise downblog.metrolinx.com
Happy to read that they're using the broadband / white noise backup alarms. A friend felt forced to move out of a decent apartment in uptown Waterloo during Ion's overnight construction period because even with foam ear plugs in the beeping backup alarms were just too much for her to sleep through. :-(