Snead has speed, but that's it. Last year with the Tides (I live in Norfolk), he hit about 230, though he set the all time franchise record in SBs (like 58 or so), while leading the International League by a large margin. If the Mets had been within a sniff of the postseason last year, I bet they would have signed him to the playoff roster strictly as a pinch runner.
He really has no fantasy value yet except in NL only leagues. If, somehow, he shows the ability to hit major league pitching better than AAA (Scott Podsednik), he could have some fantasy value, because you figure if the Mets called him up because of his speed, he's going to run. I just don't see that as very likely.