I've just got my 8820 unlocked in the mail. It's being used with a Rogers SIM card. The internet works fine on EDGE.

I've updated the software to 4.5 in DM.

However, I can't get WiFI to work to save my life.
I've been through the WiFI setup wizard and added my SSID. When I attempt to do so again, I see a green check mark and a "Connected".

Yet the WiFi symbol on the top of my home screen is grayed out and the WiFi line item on My Manage Connections icon has a yellow "-" symbol.

The connection works fine on my laptop.

I feel fairly foolish now.
I had done some searching before my post but I missed an article that resolved my issues: Calling Rogers and having my PDA Plan changed to a BB plan then having my service books pushed resolved the WiFI issue.