I try to make it a point to read and reply to the majority of the reviews my flashes get (when I can be assed to do it). I've been slacking on this recently, but I've still read the majority of the reviews, even though I haven't replied to them.
Take The Facebook Problem, guess how many actual advice-giving, helpful, multi-paragraph reviews there are in the 1,200+ that it has.
Like 9. All of which, except for the one or two giving it a 9 or 10, are currently rated useless.
It's a damn shame that the reviews that are, well, reviews are discouraged like this.