hi, i'm going to enter into this debate just because i am sick of stark white backgrounds. i used to really work hard to get that white look, and now i think it is souless. i see too many sellers "bleach" their photos with phot editing software, and it looks horrible. i make tons of treasuries, some make fp, and it is never the ones with the white background style. i think there is a new look etsy is inching towards, and it includes photos that breath atmosphere and warmth, and you won't get that from stark white backgrounds. use a piece of bleached wood, or something with a little more texture if you need that white.
what i look for (as a treasurer) is good cropping. Megan, your phots are great, clear and lovely, but stand back a little from your work. too much of the product is cropped. a little negative space around your product, no matter what colour, will go a long way in making your product pop and please the eye.
this is just my opinion btw :)