Only for the batches of emails. Email addresses starting with L's and M's were the first batches to be sent via the BCC field and there after. So my address wasn't showed
Still, the people being interviewed on the website do not show anything when searched online. And the gallery is not closed. So doesn't seem to be anything left to do.
I'm thinking it was just a way to get people's attention from time to time to remind them of the game.
This issue or mistake is just suspiciously too related to the game's own central theme to be completely ignore or labeled as a mistake. People freaked out about security issues because of leaked information. A connection was created amongst people that wasn't planned by the rules of the system. Some liked it and others said they were pissed because their gmail accounts got a security notice.
Also, it's a fictive art exhibition that took care of sending these e-mails to the real world. This is once again exactly how ARGs can be setup. When something fictional dictates you to go do something in the real world. Only problem here, this didn't dictate much. Instead, it created chaos. Are we having an ARG? If so, it's incredibly slow to start and we so far don't have any leads. Besides that hint from a fake or real joseph de marco email saying Aiden is coming (Main character from the demo). Once again, this could make for an interesting ARG narrative. The hacker(s) who managed to kill DeMarco got access to the list of mails from the attendees of the exhibition.
In any case, this could also just end up being a ploy to market the game or generate some buzz about it. This was discussed on big sites like IGN/Kotaku and it's free publicity. Maybe not the safest one,but publicity nonetheless. But ARGs are publicity themselves. Portal 2's ARG was meant to advertise the game, the Trials HD riddle was revealed as the second trials game was released. The bees ARG was linked to Halo 2.
The only thing that so far is a backup argument as to why this isn't an ARG is that there is no progress yet being made.
I got an emailed recently saying Ubisoft had cleared my email (if though it wasn't exposed) from their mailing list. And asking if we still wanted to get updates on Watchdogs to sign up on the official site.