Like Sebastien, I uninstalled the popular jailbreak tweak Auxo earlier this year. Though beautifully designed, the app switcher replacement felt a little too bloated for me, and I was convinced that it made my iPhone slower.
I do miss a few of Auxo's features though, like its revamped iPod controls and the ability to swipe down on an app icon to close it out of the switcher. But luckily, a new tweak just came out that takes care of the latter for me...