I lived right across this parking lot on Lisgar for a couple years.
This idea is a good one- it would be great to see something go on that lot which is such a waste.
However, I hope that they'll follow the Downtown Urban Design Strategy that recommended that a small park be created at the southwest corner of this lot (right at Metcalfe & Lisgar). You can see it on this picture:
http://www.ottawa.ca/residents/plann...awa_map_lg.jpg. It's a bit small, but it's just below and to the left of the #31. I'm thinking something like what they did at the Hudson, but a little bigger- maybe a fountain with some benches around it.
100% lot coverage at that location would be a bit much and that part of downtown is really lacking in open space.