Certainly these guys would agree that perfect pitch can be learned. Others, like these people, think there's more of an intricate interplay between genes and training (probably so, if I were to guess). Some of you might be interested in participating. I don't know how recent or ongoing this study is.....

There seems to be varying degrees of 'perfect' pitch as well....some people can tell you what a note is and whether or not it is a little sharp or flat....others seem to possess the uncanny ability to tell you within a few cents how sharp or flat the note is. Amazing.