I sold mine on Monday for 4500g (on Deathwing). There wasn't any in the AH at the time so I just made up a price.
I have found that it doesn't always matter what the price is so much as when the interested buyer is looking. I've reduced some pets ridiculously low and they never sold, then later they sold at a higher price. Obviously the price will matter if others have put the same pet in the AH, but if you feel they're selling too cheap then just hold onto the pet until later.
I often hold holiday pets until after the holiday is over so there aren't as many in the AH and you can often ask for more.