I'm not fond of EBAY from a lot of aspects including lofty PSR. PE, NOL's, money printing machine of option issuance, and a business model with minimal human inter-action.
Simply put, EBAY is a flying pig.
That aside, I will fully admit EBAY is well entrenched in the auction arena and your solitication is feeble to say the least.
Eh......a disgruntled group of .......eh.....P O W E R sellers having few to sell their trinkets and baubles to is more of less inconsequential to the movement of the stock price. It's about a notch above that in terms of impact to EBAY's operations.