For those avid pet lovers out there, do you like to match your pets with your different toons class and spec? I see people do this with mounts, but not as often with pets.
A sister of temptation for your warlock? a fox for your hunter? Singing sunflower for your druid or the Dark Pheonix hatchling for your shadow priest?
Though the best thing about shadow priests is you just get the glyph of shadowy friends so all mounts and pets are now a shadow themed mount and pet.
Or Maybe you prefer it to be Race based (mana wyrms for BE's) or even matching your mount, class pet or even transmog?