Full disclosure: The "Darjeeling Limited" press screening I attended offered an extra feature - the short film "Hotel Chevalier" played before the movie.
Made by "Darjeeling" director Wes Anderson, the short focuses on Jason Schwartzman's character and his estranged girlfriend (Natalie Portman, appearing briefly and tastefully in the nude - a tidbit already heavily reported on the Web).
Though the short differs in tone from "Darjeeling," it does offer special insight into Schwartzman's character, Jack, one of the three brothers traveling in India.
I didn't know when I saw the short that it wasn't included with every showing of "Darjeeling" in theaters. By then it was too late. You can't un-watch something you watched.
"Hotel Chevalier" had offered background information that colored my opinion of Schwartzman's character in "Darjeeling." Not so much that it affected my overall view of the film or my three-star rating, but it did have at least a modicum of influence.
So I would like to encourage people interested in "Darjeeling" to view "Hotel Chevalier" first. It's available for free on iTunes. It won't change your opinion of "Darjeeling," either. But it will enrich the experience.