I mean, I feel indifferent about this article.
A lot of sites already have some of these searches already on their sites, like only wanting a certain price range, sorting the price range, etc.
And we are given the capability to have our own sales and coupons, so I'm not sure why I would be upset about that? I provide a thank you coupon. And a free shipping coupon for orders over $50. I thought this is considered good customer service?
The only two I'm wth about are #1 because a) we can't contact people who favorite our items since you know, spam, b) we can't see what people put in their carts till the check out, and #9. I'm not one to do trades, unless if its a really great chances to work with someone who has a great following, but for them, since I have few followers, it won't work out for them.