To the chanter who thinks he is never OOM, what can I say? Do you EVER cast? After the buffs I mean. If you don't have FT at high end you are useless.
Do you think chanters just buff then sit on their hands? PLEASE. Slow, charm, mezz, AE stun, nuke, etc. Chanters are essential to some end encounters (think Rathe Council) but any chanter who had a CHANCE of FT and passed up FT3 boots to a ranger is a fool. Not that rangers don't need FT, but if you are not in a guild where everyone has FT15, then your guild could best prioritize FT items on the basis of overall usefulness to the whole group/raid.
Tell me now: can an OOM chanter still do damage? Not a lot really, dps is pretty minimal in the chanter melee stakes. Can an OOM ranger still do damage? Yup. Think bow and melee. Most rangers I know ALWAYS have mana because, except in very rare circumstances when they are needed to cast in encounters, they really aren't using mana that much for DPS.
As a necro I have often been the recipient of ranger heals because the cleric was busy CHing the tank. Thats probably about the best use I can think of for their mana. They often report that they almost NEVER cast and may as well use their mana for something.
In short, ANYclass at high end can use FT. I think SOME classes without the natural mana regen of a shammy or a necro might be prioritised. Certainly clerics come to mind, but EVERY caster needs FT. Some just need it more than others.