To the second part I would have to say no. There have of course been times when on first listen I've been knocked out by an album but then going back to it somehow it's not as good --- I think I mentioned this in my "Fortress of Prog" thread with respect to Delusion Squared --- but generally if I really like an album first time I think it's great that I do, and I know I'll be listening to it again and again. This is how I felt with Ten, Mostly Autumn, Kamelot and Arena. No, you don't know any of them...
I don't think there's any album or song I loved immediately that later lost its sparkle for me. But maybe that's just because I'm an old codger (seriously: is that word really a shortened version of "coffin dodger"?) and set in my ways.