This is the third update to iTunes 12 and has a build number of 18.104.22.168-- the second build was 22.214.171.124 while the first release was 126.96.36.199. Like the second update, Apple has not released a change log with this new build (it simply posted the old one under Software Update), but so far we've noticed some small font changes, as well as improved performance/stability.
For those with iTunes 12 installed, you can get the update by select Software Update from the Apple menu at the top left of the screen.
Let us know if you spot anything!
New Clean/Explicit tag icons