I have a feeling the delays are due to the ongoing negociations with Sony/BMG. I think Steve will try to negociate until the very last minute and should that fail, will open the store without any Sony/BMG stuff and add that later.
I don't expect any announcement, except perhaps for a press release. They'll just throw the swith on and run off home with the hope that no angry Canadian will attack them before they realize the store did indeed open.
At this point though, I have a hunch they'll delay until next week or perhaps even a bit later than that. I think Sony/BMG is a big piece of the puzzle to be missing and maybe they want to wait for them before opening the store.
Either way, I doubt the delay is caused by Apple. Technologically, they're ready... all that'd needed now is the OK from the lawyers.
Basically, we're screwed 😀