Fantasy Upside
Geno Smith is in front of Ryan Fitzpatrick on the depth chart. That could give him playing time sooner rather than later. And he has done some good things as a starter during his career.
Fantasy Downside
Fitzpatrick will throw three TDs one week and turn the ball over four times the next. He is not afraid to sling the ball around the field, but that has equated to a lot of turnovers during his career.
Bottom Line
There is not much value for Fitzpatrick until he becomes the starter, which might not happen right away. If Geno Smith fails, Fitzpatrick could be decent depth in deep leagues. Most likely, he would become the featured QB the rest of the season.
UPDATE:
With Geno Smith sustaining a broken jaw, Ryan Fitzpatrick steps into the starting role for New York. This does not make Fitzpatrick an option for your fantasy team, but it is something to keep an eye on early in the season. At this point, he would only be valuable in leagues where you need to carry more than two quarterbacks. Plus if he doesn't perform, Smith could get the job back for the second half of the season.