Not sure yet. 11main.com in particular has a more "local" feeling to it style-wise. I find it aesthetically pleasing to look at, instead of the blocky old look/feel of amazon.com.
I think 11main.com is only their first recon assault wave. More will come.
Alibaba is the parent company for a lot of child companies -- they have an equivalent for most of our major US companies[1]
It's a little intimidating when you realize the scale these guys are playing at.
[1] http://qz.com/206283/all-the-western-companies-youd-have-to-...