After I got hit with the Blaster virus, my sysop 
advised me to manually reset all my passwords for 
things like this that involve money: eBay, 
PayPal, etc. Because my computer had been 
accessed from outside due to the Windows "hole," 
he said it was possible that someone could 
observe or recover these passwords and then use 
them to block me out of my accounts, or, worse, 
charge up expenses to me.  

So it seems as if eBay is being proactive on your 
behalf.