The old Movie Trailers Plug-In was obsolete and was way below what the public demanded and could find using other means and other places. Because user comfort is one of the more important features that determine whether he/she stays on a site or continues using a service or migrating to another, at least for that particular aspect he/she is less satisfied with, the Yahoo! Instant Messenger development team decided that a face lift and a shot of technology right in the vein should put the patient back on its feet.
That said and done, they have rolled out the new Movie Trailers plug-in just before Christmas and they let it run amok in the film fans' ranks. And that it did. "This new version has larger movie posters that you can browse through; just click a poster to watch the high quality trailer in an adjoining window. You can also read a brief synopsis of each film, right in the plug-in window. Best of all, the performance of this updated plug-in is much better. If you're on a broadband connection, trailers load instantly in widescreen view with little to no buffering", Sarah Bacon, Product Manager, said in a blog announcing the update. Additionally, you can use the feature to find out where the movie whose trailer you are watching is playing and the place that is the nearest to you.
The plug-in is only available for the latest versions of Yahoo! Instant Messenger, namely 8.1 and 9.0, so if you're not using one of them, be sure to download the client and install it prior to adding the Movie Trailers.
On a different note, the feature to browse and view a trailer with a friend in the IM window while you chat has not been finished working upon and will most likely be added with the next update that will be made available.