I usually read through a game enough to get a feel for the game. (Sometimes that's the entire game, sometimes it's just a few sections to get an understanding what it's like.)
Then, if I feel the game is compelling or interesting, I put it in my "Games we might play sometime" Google doc, with a paragraph or two about what I find interesting about the game and a link to where it can be found. Sometimes, when discussing potential games with my friends, I'll share the document to them. But mostly, it's for me to keep track of games I haven't tried yet that I would like to do.