Downloaded app updates not copying back to computer automatically

Since upgrading to iTunes 11, I've noticed that if I download an app update directly on either my iPhone or iPad, the new version does not copy back to my computer the next time I connect it. It used to do that automatically (the older versions that were already on my Mac would automatically be transferred to the trash) and I did not have to make the extra step of doing a separate download on my Mac. Is there a setting somewhere that I need to correct to bring this functionality back?