In all likelihood, Cole is looking at a fine and nothing more. Had anything more serious been in the cards for Cole, I'd have to think the FA would have been more hesitant to allow him to play in the upcoming World Cup qualifying games.
After the ridiculously long (and still going) saga involving John Terry, it's nice to see this situation being wrapped up fairly quickly and painlessly. I'm sure that most of the media will still criticize Cole for, well, everything, but at least he's handling this situation very well. That's certainly a nice change of pace, isn't it? Hopefully this was the last twitter related miscue we see from Cole, or at the very least the last one while he's a Chelsea player.