I was recently informed by my boss that, following our site redesign a month or so back, there were some outdated URL's from the old structure still appearing in Google.
Will they disappear in time?
If not, does it make sense to fight them, or is it better to use the 404 page to convert them to true visits?
If it make sense to fight them, how? Da boss said something about robots.txt. Since I'm not a webmaster, but rather an SEO neophyte who must work through a (willing, thank God) webmaster, the thought of tinkering with robots.txt makes me shake in fear...
They will disappear eventuelly after this update or the next. In the mean time you don't want to show your visitors a dead end so it's best to show them a message and redirect them to a new page. Nothing to do with a robots.txt.