One thing that irks me about ebay's feedback system is that most sellers wait until you have left feedback before leaving any for you as the buyer. If I'm the buyer, my only obligation is to pay via the agreed upon terms in a timely manner, no? So as soon as that is done, the seller should leave me positive feedback. Instead, they wait until you leave feedback and if your feedback to them happens to be neutral or negative, they retaliate.
For instance, I recently purchased a tool on ebay that I need to finish this kitchen remodel. I need to have this kitchen DONE by June 6th. I bought this tool on May 24th, paid via Paypal instantly. The seller is in Iowa. I've emailed him twice asking about when it will be shipped. He claims he shipped it the same day (May 24th), but that it will take 10-14 days to get there. I paid this guy $50 for shipping a medium weight, medium sized tool and it's going to take two weeks for it to get to me from Iowa?! That seems bogus to me.
When the tool arrives, I'd like to give him a neutral for poor shipping (assuming the damn thing works in the first place!) but I know he'll then turn around and give me the same or worse, even though I upheld my end of the bargain to perfection.