Butterfield is definitely my top pick of the current batch. Right age and height. And even has a bit of that Ditko inverted triangle head shape. If they pack 15 pounds of muscle on him he'll probably look perfect. The bigger question is his acting. He's a bit whiney sounding, which might not be a bad thing because he shouldn't be a deep-voiced adult. He was able to pull off awkward science nerd and tortured soul in Ender's Game. But that doesn't mean he doesn't also have the range to also do snappy, wisecracking Spider-Man.
I agree Garfield was well cast and very likable in the role. And I also really liked Emma Stone. But I much prefer the idea of a teenaged Spider-Man.
I would imagine the announcement will come any day now.
I also hope they go with a higher tech costume design more like this one.