I mean on a pc, task managers are used to kill hanging processes that might cause your system to stall a little bit, but that's only if your applicat
While I respect your opinion comparing Windows to UNIX and its memory management is not possible as Windows memory management and multi tasking is pure garbage as compared to any UNIX variant.
If you find that you need a task killer to maintain performance, dont blame the OS, it is most likely a poorly coded app. With the Android marketplace accepting any and all apps (with no regulation over poorly coded apps) it is caveat emptor.
Dont blame the OS but, the lack of Googles supervision over the marketplace is the problem here, and consumers then turn to task killers to compensate for poor coding.
JMO.