My exactly 2 cents:

# The concept of UGC is that anything that gets gamed is undone by the good contributors (at a stage with good traffic), initially community managers/content would do the policing for such things.

However,I’d like to know the various ways in which such a system could be gamed by somebody. Also the precautions that should be taken.

# The best way to tackle credit card inhibition is to get every merchant involved with a COD. Thats one of the ways e-commerce can overcome the mindset hurdle.

Keep posting!

Another aspect to the ecommerce phenomena in terms of providing value to the customer – if a group of friends are convinced to buy a product online they should see an incentive for buying the product together (in a community). It is like going to a wholesale club Sam’s Club (by Walmart). If I buy 5 pieces of the same product together I should get a better deal with greater discounts. This feature could enable groups of people collectively make purchase decisions.