When Apple unveiled their multitasking bar in iOS 4.0, they were fairly late to the party. As with multiple features, the jailbreak scene had already had multitasking apps like Backgrounder out for a while. Although it was belated, a lot of people really took a liking to Apple's new multitasking support.
Then there are people like me, who are constantly searching for a better alternative for switching between applications. Sure, there are apps like Stacks and Dock that make multitasking easier, but is there anything else available?