They have a fully documented API (http://trakt.tv/api-docs) so it shouldn't really be a massive chore the have the video player report back the currently playing title. I did post in the features request section but didn't get any response so BKKKPewsey suggested I post it over here.
Its something id love to see and could be very useful
Is there any modder that would be interested in this? I could try and do it myself but im far from a professional or even half way decent coder so while I understand the basics of how this works doing a decent implementation of this would be quite hard for myself.