I can tell she has bigger boobs in the second pic, but there are a lot of other differences, for some reason her face looks better in the second pic and that was actually the first thing I picked up on, half a second before I noticed 'oh, boob job, that's what this is about'.
but in the first pic, she has a longer looking diamond shaped head, with rattier looking hair done in a weird hair style that looks almost like a mullet.
if I put my hand over the head, between just the bodies, yeah, I guess the lower one is a bit more appealing, but I did have to think about it for a sec.
breast size is not some direct simple measure of beauty. when I try to explain this to girls, the best I can do is big breasts vs little breast are like two different flavors, some times you want chocolate sometimes you want something fruity, it just depends what your preferences are and what you are in the mood for.
honestly my criteria for judgment goes waist size -> face -> breast. and (like I said already) bigger is not better, some girls look better with smaller breasts.