I have heard people say that this use to be a very nice place in Brussels, but as as far as I can remember the square is a permanent construction site, and some people referred to it as "ground zero". Does anyone know why is taking them so long to finish what ever they are trying to construct there. I am starting to think that the NYC world trade center will be reconstructed before work is finished in Flagey.

Good question. The place still looks like a bombsite and no progess is obvious even though "wrokmen" mill about the place. "Work in progress Belgian style".
The autoroute to Mons is another classic example of Belgian inefficiency. Orange "temporary" road-markings have been there for months with no obvious sign of any work in progress.