Becoming listed as a seller on eBay is a tad more difficult than becoming a buyer. Here's about how it works:
You either have to become a PayPal customer which btw includes PayPal access into a checking acount you own. *or*, you can elect to be certified as existing by an SSL CA, usually Verisign I believe. What eBay is trying to do is prevent shady sellers. Not a perfect system, but about as good as you can figure out with high speed commerce between people who do not know each other.
The problems of reliability of both buyers and sellers, and the candy and cavity of methods of payment is a subject for more detailed discussion and alternatives. Hope this helps.

Have to agree (mostly) with Zeroth, PayPal is a *major* international financial player and cannot afford to get a *valid* reputation of messing up peoples bank accounts. There is a lot of negative reports on the internet regarding PayPal, however I am not convinced they are not largely the result of problems *not* created by PayPal.
"With that said", ;-) I have made a couple of telephone contacts with major (thousands of sales, 99.99-100-percent green comments) sellers on eBay as a result of winning bids on their items. Without fail, they say that their problem is having a 'buyer' later (few days) make a cancellation of payment with PayPal, falsely claiming anything that would normally get a sale cancelled. Also, without fail, the merchant has an amount equal to the sale 'frozen' in his account which of course makes it unavailable to him. Also, without fail, the 'buyer' does not return the merchandise, so the seller is out of his merchandise besides all the hassel of being conned.
OK, fast forward to a conversation I had with a PayPal account manager on behalf of one of my webhosting clients. He explained that they (PayPal) dilligently try to negotiate such arguments between sellers and buyers, trying to be fair to both and keep both from getting scammed. He said they had recently established several offices solely for the timely resolution of these difficulties. (Which, I suspect, are an extremely small sub-percentage of total sales.)
The 'rest of the story' from the sellers relating these difficulties is that they began checking the profiles of energetic bidders, to see if they had any negative reports from other sellers, or in the case of someone bidding with only a few prior purchases graded if there was a believable 'About Me' page for sellers to see.
One of the sellers I spoke with said he only kept 500us in his account so that not so much could be frozen. Another one said he quit taking credit cards and only accepted postal money orders and certified checks. (That probably means he had to establish identity with Verisign in the absense of a PayPal account). There is also a difference between a 'bank account' and a 'paypal account'.
I have had no problems with either eBay or PayPal. Of course they are the same entity, eBay bought PayPal, as you know. I suspect that PayPal by now is up among the Citibank etc rarified atmosphere of financial players. But that's just a swag of course.