There have been hints before, but now it's fair to say that Final Fantasy VII and Final Fantasy VIII are almost certainly coming to Steam. The SteamDB page was updated yesterday to include a set of logos for both games. This is on top of each game receiving multiple updates over the last few months, and Final Fantasy VIII receiving achievements.
via N4G: pc news feed http://n4g.com/news/1246789/final-fantasy-vii-viii-definitely-coming-to-steam-logos-added-to-db-page
via N4G: pc news feed http://n4g.com/news/1246789/final-fantasy-vii-viii-definitely-coming-to-steam-logos-added-to-db-page