Over the years I've read around various forums quite a bit and paid close attention to what is said. There is a general favorite, that being about 7" length for white women and 8" length for black women and some extra thickness to thick for both. When it comes to girth women tend to talk in 'thickness' terms and not put a numerical label on it. 6" length actually does quite well, and 8" length does well also. 5" length is sometimes said to be too small, but 9" length is sometimes said to be too big. It has been very clear that the vast majority of women prefer at least some extra thickness, and many of those prefer it to be thick. All that is just in general. It can vary quite a bit from forum to forum.
For instance, at Ivillage most of those women will tend to push the size isn't important part and focus strongly on relationships. If someone presses them about whether size counts even if its not important they will pretty much go into a spill about the clitoris and hands and tongue and keep bringing up relationship importance. If asked again they will say something to the effect that everyone is different, but that size usually only matters to a few rare size queens. Just like LPSG as a whole doesn't quite represent what most women tend to think, IVillage is on the other side of the spectrum and doesn't quite represent either. I like reading what the ladies at BET have to say now and then, as they tend to post in a no holds barred fashion. At that site 6" seems to be the lower limit in length for most of the ladies. 8" length and longer tends to get a very good rating. At least some extra thickness is preferred there. Reading around about this topic at many forums it's a mixed bag. Combining this to what I've heard or overheard in the past at parties, work places, college, cafes, etc. Also, size queens make up about 10% of women. The lower cutoff in length tends to be 5" for the white ladies and 6" for the black ladies. I could go on, but I'll stop here.