Google announced via Google+ update today that it has added a "Trailer" button for movie search results, which let you watch a trailer from YouTube without having to leave the search results.
Here's the post:
Finding the perfect movie for your next excursion to the theater just got easier, thanks to an improvement that enables you to watch trailers directly from the search results page. For example, if you want to check out all of the movies available in your area, you can search [showtimes nyc] on google.com in English, click the Trailer button next to a listed movie, and the official trailer on YouTube will pop up. If that movie's not your cup of tea, you can click the X in the right-hand corner and watch the other trailers available. The Trailer button is also available if you're searching for a specific movie—say, [finding nemo 3d].
When you click the button, it blacks out the screen and serves you a YouTube video with a movie description. The look is very similar to when you look at a photo on Google+:
This is just the latest example of Google finding more ways to keep you on Google, without having to send you to a third party site (although in this case, Google also owns the third party).