The -> in ViewPatterns binds more weakly than infix data constructors.
The following code, essentially taken from the ViewPatterns page on the wiki doesn't seem to parse correctly.
mymap f  =  mymap f (x : mymap f -> xs) = f x : xs
However, this does:
mymap f  =  mymap f (x : (mymap f -> xs)) = f x : xs
(though it triggers bug #2395 (closed) about overlapping patterns)
It would seem nicer to make the view pattern arrow bind tighter than any infix data constructors.