> The goal must be [...] multiple content processes for each tab

According to the wiki page you linked, it doesn't seem to be the goal for them:

"The (practically) unlimited process count is on some platforms not a realistic goal, and having a separate process for each open site instances or even sites does not seem like a reachable goal (for now at least). Which means using content processes as a security membrane cannot be a goal either."

If this is true, I don't see any advantages of e10s introduction.