Pets - Did you used to do the Vendor pet sales? How have pet battles changed things for you?
I very briefly dabbled in selling vendor pets on the AH. Before MoP hit I was busy collecting as many pets as I could ready for pet battles. This included flying around getting any vendor pets I'd missed.
I was missing the three moth pets from Sixx in The Exodar. These moths can be purchased for 50 silver each as the Yellow Moth Egg, White Moth Egg and Blue Moth Egg. I remember that I asked in guild chat if anyone wanted me to grab them one of each whilst there and one person said yes. So I bought myself one of each, my guildie one of each and a couple of each spare - to try out selling vendor pets. I sold them on the AH for around 15g each - which I was fairly happy with.
I went back to Exodar and ended up buying some more and re-sold them. I'm not sure how many of each I re-sold but I stopped when someone else also started selling them and under-cutting me - they were inevitable spending more time at the AH than I was.
Since MoP and pet battles I haven't tried to sell any vendor pets. I guess I was just experimenting with the market and it went well for me. Now there's a lot more people trying to sell vendor pets on the AH so I probably won't try it again until the markets less saturated.