Here's an interesting aspect of long-term game development: if you build a game where you're continually adding units across a number of years, you will see a marked difference in model quality between the first creations and the newer models. It can't be helped. For some games that might not matter, but World of Tanks is about tanks and the people who love to pay for them, so it benefits Wargaming to ensure that those earlier models are returned to the high standards of the latterly built ones. That process has been captured in a video, and there's a lot to be excited about if you care about polygon counts and the smoothness of tank barrels.
It's really interesting stuff. There's more to it than just tweaking the poly counts: they 3D scanned tanks and talked to historians about crew movement so they could accurately represent scuff marks. And for tanks that never existed, they used their knowledge of the nation's armour, the time period it's from, even information about what factory it was built in, to speculate as accurately as they possibly could.
Warning: it's cheesier than a French fridge in a powercut.
I guess the video has done its job, because I am now redownloading World of Tanks.