An equally important question is "when?"
I don't understand why this part is overlooked. Getting ICS within a month of release is not the same as getting ICS 12 months after release.
I am also more interested in when. I can only make wild speculations based on history. The first phone to feature ICS will be the Galaxy Nexus which will begin being sold around mid-November. In the past it has taken around a month for the previous gen Nexus to get the OS update. I'm holding out hope that the Nexus S will get the update by mid-December, but that is just speculation. As for other carriers and manufactures, there is no telling when upgrades may come. Upgrading people's phones with a better OS does not exactly help sell phones so I'd bet a longer wait for those without a Nexus S.
At this point I'm more interested in which devices some future Cyanogen release of ICS will support.
Given the history of android update promises "confirmed" is probably best saved for when ICS is actually available for user update.