Good luck ...
Early on in my travels with Linux I though it might be interesting to have a look at the mm code. Drove me to drink. Several times.
Not having looked at that specifically, I would imagine the implementation merged, but the functionality remained - things still need to be tracked. It is notoriously difficult (nay, near impossible) to get changes into the kernel base. Everything else that currently works still has to work, as well as proving what is being introduced is a) useful, and b) does (only) what it is purported to do.
So don't worry about the side issues, concentrate on the real task at hand. There are innumerable ways to get side-tracked in mm.