I plan on first using mine on the Red Cricket, because when Sho gave me my gift it ended up being a grey one :( After that, it would just be a few of my favorite pets that start as green quality, such as Wolvar Pup, Peddlefeet, or other similar "quest" pets that you can't get any higher. I...

5.1 is indeed today, and found this post off of http://www.reddit.com/r/WoW detailing all of the new pets and where they come from, hopefully this site can update soon too!

http://www.reddit.com/r/wow/comments/13v94h/compiled_list_of_51_pets_complete_with_locations/