The big thing with Panda is that they are going after duplicate content and poor quality content. If changing the URL structure or redirecting everything to the new domoan or subdomain works, it will probably only be a temporary fix at best. Crappy content is still crappy content, no matter where it appears.
I'm more concerned about their November 3 update, which some sites are calling Google Fresh. That appears like it will be demoting ranking for stagant content and sites that do not regularly add content, and that in itself could be a disaster for most business sites that do not regularly add content.
Giving you fresher, more recent search results
Someone over at search engine watch thinks this will affect 35% of sites, which makes it potentially big. As we have seen too many times in the past, collateral damage can hit almost any site.
Google Gets Fresh with Algorithm Update Affecting 35% of Searches
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin