I saw your post in my earlier G20 thread. Are you getting married at St. Michael's Cathedral?
If so... if it makes you feel any better, I don't think St. Mike's will be quite as directly affected. But it may be a hassle for any guests driving in from the west so you may want to help them look up routes to circumvent the security zone. Hopefully you don't have any OOT guests in the G20 hotels, or if they have, hopefully they've been advised to book elsewhere...
Sorry dude. Feel free to ask any specific questions. What a hassle!
Baby #2: Surprise BFP 9.19.12, EDD 5.24.13, natural m/c 10.19.13 at 9w