Whoa. I'm the author of this 2048-game.el (the one in MELPA; there are many implementations), located at https://bitbucket.org/zck/2048.el. The coloring is definitely something I've wanted to add to the game, but was holding off on for the moment.

Why? Scoring. 2048 has a score that's also a number. So if you colorize only based on keywords, you'll color the score too. And that's bad.

Edit: I'd happily take patches, suggestions, or pointers to documentation on how to do the colorization properly. Email in profile.