I don't 'discover' apps -- I always download a specific one I'm looking for (based on external reviews, friend's recommendation, etc). So these interstitial pages are rarely useful to me.

I suppose the answer might be different if I were downloading an app I've never heard of before, but I am also having difficulty imagining why I'd want to do that.

Good grief no. A better solution is a "help" menu item.

I usually try to skip but I guess I'm a heavy user, like most here.