Taobao is an eBay like site based in China that sells all the items China makes for every company. Items can be released on Taobao over a wide range of time, from months before an item's release date to well after an item has been retired. Quality tends to vary from store-quality to factory items with mistakes.
In the My Little Pony franchise, Taobao has served as a semi-reliable source of upcoming G4 toys, due to the tendency of Pony toys to appear months before their official release. Taobao has also served as a source of extremely rare varieties are factory rejects due to such things as having the wrong head, body, hair, or cutie mark.
taobao shops with ponies:
When blind bag ponies were extremely under circulated Taobao sellers started selling the figurines as key chains.
White Blank Baby, Sweetiebelle body with Fluttershy head 
Glimmer and Style Variants
Taobao Exclusive Characters
G4 Minty (we are still waiting!)