A feature for following actors/directors, so you could get emailed when they're in/making a new movie

Wouldn't that be great ?
And besides of keeping track of new movies of/with your favorite actors/directors you could also keep a list of them (just like the watchlist) 
and maybe there even could be an (optional) email-newsletter for imdb-pro users (who are more likely to be interested in this) that aggregated all activities of the actors/directors you tracked such as nominations/news/..

By this imdb would upgrade to a more modern version that implemented very promising features that are widely implemented on twitter for quite some time already.

betterific.com seemed to like this idea: http://betterific.com/psYbb/IMDB-allowed-you-to-follow-actorsdirectors-so-you-could-get-emailed-when...