It's pretty retarded for anyone to even consider selling Cas coins through Ebay. What usually happens with these coins is that the owners list their coins just for the sake of getting that exposure, then settle the transaction in real life or in a different manner, everything but through the regular way items are usually purchased through Ebay.
There was a stunning 10BTC Cas listed on Ebay for $300,000 not that long ago. Not sure if it got removed because it sold outside Ebay or that the owners removed the listing because the price went down.
In UK Ebay any attempt to list a Casascius coin for auction or buy it now is flat out rejected. You can only list it as a classified ad. I can see why to an extent but it's a pain up the arse if you have an empty one and fancy auctioning it.
Other Ebays seems to allow the usual formats.
Is there a browser-based version yet?
I've seen browser based searches but there's no way the project itself would support a full browser version. No one would bother running the client so the whole thing would seize up.