Nowadays, we are using multiple core systems. We must write our .NET applications in such way that we must utilize complete computing power of machine.
The task parallel library(TPL) allows you to write efficient code which is human readable, less error prone, and adjusts itself with the number of Cores available.
So your software would auto-upgrade with the upgrading environment.
It also improves the readability of the code and thus reduces the risk of getting bugs which makes solving difficult and time taking.