The Indian restaurant being knocked down is on the west side of Yonge north of Park Home, for the Centrium condo + hotel.
The "messy office" mentioned before is, if memory serves me correctly, temporarily being used as a condo construction office.
There's really not very many redevelopable sites left in the North York Centre zone and developers are busy consolidating whatever lots are left, which may explain some vacant storefronts.
The condo base retail spots are invariably worse than the retail spots being torn down, as well as probably being more expensive and a bit more stifling in terms of what goes into them. Yonge can't afford to lose many more blocks of pre-condo retail buildings...losing the block with the Mr. Greek, Bar Burrito, etc., would be a disaster. There are a few spots, like where Centrium is going, that can afford to go because the existing retail buildings are in poor shape, don't meet the sidewalk, are filled with parking spots, etc.
Some of the retail units in Pulse and Grande Triomphe, closer to Finch, have sat unoccupied by a year or more. The local population has basically doubled in the past decade, and threads like this prove there are entrepreneurs looking to open on Yonge, yet some condo retail units sit and sit and sit. The Triomphe retail units are shoebox-sized but the ones beneath Pulse seem quite large, so I don't know what the problem is. Maybe the leasing rates/regulations.
It'd be nice if when a development begins, the developer made an effort to relocate the dispalced store and retaurants within the same community, but I'm not sure this ever happens...there's no obligation, anyway.
Long term, it might be worth trying a site north of Finch...if the subway is extended, foot traffic along Yonge will dramatically rise and the wall of condos will march north.