If sellers pulled currently listed items, they would still owe fees. My understanding is that the boycotters will not be adding any new listings during the boycott week.

As for chip sellers boycotting, I can only speak for myself. I would like to support other auction services, and have been experimenting with Jackpot Auctions recently. I have sold some items there, and have purchased as well. To move all or most of my business from eBay to Jackpot, I would need to see more buyers active at Jackpot. I plan to continue supporting Jackpot as part of my mix, but even with higher fees I can't exclude eBay if it delivers more bidders. More bidders = higher selling prices; higher selling prices = a greater ability to absorb eBay's increased fees.