Why does XCode 4 include the file extensions and @2x suffixes in the image lists?

In previous versin of XCode and开发者_JS百科 IB, when I would specify a background image for a button, the image lists would just include the filenames without the file extensions or @2x suffixes and the iOS was smart enough to know which file to use depending on whether or not the device had a retina display. Now in XCode 4, when I go to select an image for a button, it lists all the images in my project, including their file extensions and @2x suffixes. Which one do I use? If I choose the image without the @2x suffix, will iOS know to use the @2x version on devices with retina displays?

Thanks so much for your wisdom!

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Choose the ones that don't have @2x. That seems to work great for me. Like you I have no idea why apple decided to start including all file names in the results list. It seems quite counter intuitive.