In May Chess.com “quietly launched” a free educational poker site named Gambit, reports The Verge, where players can learn the game and improve an Elo-like rating without risking real money. And next Chess.com will expand into more classic games, including go, backgammon, and mahjong: Like Gambit, Chess.com is developing Elo-style rating systems for these games, as well. [Chess.com’s chief growth officer, Albert Cheng] didn’t say when the new sites will launch but that “development is moving quite rapidly” on them, using the same playbook he used for Gambit…