I've been buying and selling on ebay for many years and shill bidding is prevelant in all areas. I had a guy bid me up under a second name. The funny thing is that when I received his email about winning the item, his actual email address was the shill address he used to bid me up. When I checked his other auctions, he had done the same exact thing almost every single time. I reported him to ebay and he was suspended. btw- I didn't pay for the item and guy didn't seem to mind.
I also see many auctions that are constantly being relisted that are private and have 1 bid each time (the Allah domain comes to mind). It's a sad but true nature of the beast.
Any edge to get the extra buck. If someone bites, that's great for him, if not, just relist for free. If he gets suspended, create a new ID.