I too got the initial email from e-CAS tracker "subject line was: e-CAS Tracker now active" like the next day after my sponsor got the email approving sponsorship. Now today I've gotten my second communication from e-CAS tracker, namely that "e-CAS Tracker case now showing." It says that the latest update is: "We received your application for permanent residence on June 9, 2011."
This would correspond with the part in the sponsorship approval email letter (how about e-letter) about Missassauga forwarding it to Buffalo, if indeed the "we" in that sentence refers to the Buffalo VO. Hopefully this latest development means that an AOR will be the next thing I get from the VO (I'm expecting a one month wait for approval from MICC, which would be the next thing I get, I hope!).
From my (relatively cursory, maybe, but still...) experience around these boards and understanding of this process, I think that the AOR might very well be one of the least understood aspects of the Family Class application and process. I'm not even sure that I'll get one, as not all VO's send one (this is a snail mail letter) and Buffalo has been talked about as one of those not always sending them out (ah, consistency CIC, consistency...). Then what the standard language of the letter is and when it usually comes - I've read responses that run the gamut on that, so I'll reiterate my belief that AOR is up there as the least understood part of this thing.