Some examples: Manhole, Mario Bros., and, of course Snoopy Tennis. What's particularly nice about this is that we now have Nintendo games documented in a relational database from 1980-1981 all the way to the present day. Hopefully we can do more with this data in the future, but in the meantime, great work, y'all.
One MobyGames contributor who's been on the site since 2014, largely contributing user-taken screenshots (a rarity nowadays!) is Twitek, and he now has over 2,000 screenshots added.
His particular concentration on Commodore systems has meant all kinds of useful screenshots that may not be available elsewhere online right now, from Tynesoft's Autobahn to the fun (& relatively new!) Sheepoid DX plus Woolly Jumper, as well as the super oddly named Joe & The Serif. Anyhow, thanks to him - and keep up the great work!