This answer might spawn a whole new question itself, but I believe the notion of Perfect Pitch vs. Relative Pitch and how one obtains Perfect Pitch is a very debatable topic.
Until recent, it had been thought that one is either born with Pitch or was not and that it can not be learned, and that any attempt of learning it would only result in a person having Relative Pitch. However a study has been released that refutes this.
The study can be found here.
Quotes of the article are as follows:
In a study published in the Journal of the Acoustical Society of America and being presented at the ASA meeting in Portland on May 21, Deutsch and her coauthors find that musicians who speak an East Asian tone language fluently are much more likely to have perfect pitch.
“Perfect pitch for years seemed like a beautiful gift – given only to a few genetically endowed people. But our research suggests that it might be available to virtually everybody,” Deutsch said.
Unlike English, many East Asian languages, such as Mandarin, Cantonese and Vietnamese, are "tonal," so that a word’s meaning often depends on the tone in which it is said (not to be confused with intonation such as sarcasm). Deutsch surmises that learning perfect pitch is, for fluent speakers of a tone language, akin to learning a second tone language.
The study follows up on one Deutsch did in 1999, which found that native speakers of Vietnamese and Mandarin exhibited a form of perfect pitch in enunciating words, which led her to hypothesize that pitch was an extra-musical ability. Deutsch then set out to investigate perfect pitch in music. In 2004, she found that students at the Central Conservatory of Music in Beijing, China, all of whom spoke Mandarin, were almost nine times more likely to have perfect pitch than students at the Eastman School of Music in New York. That last study, however, left open the question of whether perfect pitch might be a genetic trait – since all the Mandarin speakers were East Asian.
Overall I believe this is still a highly debated topic that I find extremely interesting and takes a role in the comparison between those with musical talent and those who who are without musical talent and if it is not genetic at all.