I think that both Paypal and eBay are focusing so hard on buyers these days that they are missing the point that they are alienating the vast majority of their sellers. Right now, they have the marketshare and muscle to cause enough orders that sellers will stay with them. But they are RIPE for being taken down by another service that is more seller friendly. I am an eBay Powerseller and I know of very few other sellers that would not leave them in a heartbeat were there a business that had the buyer traffic that they have right now. And there are some big players out there that could do it, if they wanted to.
I sold hundreds of items on ebay, but now I'm suspended by ebay, cause I didn't meet their feedback percentage in one given month. Which was the christmas month, which 2 or 3 buyers gave me negative simply cause they said shipping was too slow, which was kind out of my hands, cause postal is slower during the holidays. One person even said Slow Shipping, Great Product (Negative). Lame I don't know about paypal being buyer friendly, yes in the case if it's a ebay transaction, but In general I just think they care too little and always just look for the easiest way out for them when there is a dispute.
I have a little faith in paypal, Someone hacked my account and spent almost $200. I got every cent back.