I think I know what happened to this one
Listening to the Q2 Allied properties, they mentioned this site directly in regards to the joint venture with riocan
http://business.financialpost.com/2012/07/16/riocan-allied-properties-team-up-to-develop-mixed-use-properties/
You can see the article above mentions "King and Portland" in the press call they mentioned 620 King West.
They went into more detail, they said a condo developer was in the process of acquiring the site but gave up (not much details here) and they and riocan are in the process of acquiring the property ... its not clear if they already bought it or not. But if this is the case this project is dead ... moreover they indirectly hinted they have no interest (allied that is) in perusing joint condo / office projects (it wasn't directed at this acquisition, rather a general statement after someone asked the question) and would rather focus on office + retail (with riocan).