Seeing as they are planning a 37 storey across the street from Loblaws as part of the East Bayfront plan I would expect 25-35 storeys would be tough to block at the OMB, especially with London Condos at about 30. I doubt they will get 46.
The locals wanted London to be it for tall buildings as you move eastward along the Esplanade. They've been fighting tooth and nail to keep the sw corner of Church and Front from being too tall. They won't be pleased with anything taller than 10 or 15 stories here in keeping with the buildings on both sides of this lot.
The St. Lawrence charette (2005?) made it clear that this site is ok for a tall tower on the south/east part of the site since it has almost no impact on neighbours... shadow or otherwise... it's right up against the rail berm. Presumably it will step down to the municipal parking lot which will hopefully become a park (charette recommendation).
They'll probably have to it shrink it some to appease the usual suspects, but I see only benefits to the St. Market specifically and neighbourhood in general (the park would be fantastic here)..
A 30-40s is probably ok for this site, considering that's going to be the pattern for all the intersections at East Bayfront anyways. I can see the Crombie Park Expansion being a potential Section 37 carrot - perhaps they should up the ante a little and ask for some additional capital funding for renewing the entire park.
I don't necessarily object to something tall if it's pushed right up against the rail berm. 46 storeys sure is massive, but it seems to be becoming the new standard height for condos in Toronto. Do we have the more detailed planning report available for this project?