Collective Ecommerce & whats missing

As per Wikipedia the word Collective means a group of entities that share or are motivated by at least one common issue or interest, or work together on a specific project(s) to achieve a common objective. My question to reader is that is this same as Social Ecommerce, for example kaboodle.com.
People come to shopping sites to shop smart goods in reasonable price. How its effective in Social ECommerce
Arguments why its useful,
  • One buy a product if his friend recommends
  • One can write comments about good or bad about product and that might meaningful to their friends
  • One can keep in wishlist and which might be interesting to others
Today Social network is grow-up more than one's real network and its missing one part is same mind people. This is often happens that I do not like all the choices of my best friends shops. Reason is that we might match by 80% and so our choices are different by 20%. Also this not necessary that you will like to share everything to your friends.
It will be interesting if your shopping behavior matching with someone who actually out of your network. I think future collective Ecommerce will address this needs.