Many people are panicking and asking for link removals or even changing their URLs for their entire site. This proposes how you might switch a site (using SiteBuildIt) to another new domain.
While you might lose some traffic, submitting a change of URL in Google Webmaster Tools should help mitigate the issue of authorship, esp. if you continue to own the original URL, too.
For example, I might move my content from my Coffee B site to Coffee A site, then set up the change of URL in Tools for Google’s benefit. Now that my Coffee B site is no longer used, I’d set it to NPI, and redirect the domain to another (BlueHost?) hosting account, where I can do things like a site redirect with no follow in the tags.
There are huge intricacies invovled: first, you would need to move (download/upload) all your images, recreate all your C2 content EXACTLY, set up your tracker links, AND make sure your new file names matched the old ones EXACTLY.
But with a domain redirect (if you don’t know how to do this, don’t ask SBI… it’s only something that can be done on regular hosting), a file at CoffeeSiteB/cool-drink.html would redirect exactly to CoffeeSiteA/cool-drink.html, a tracker link would also similarly work, and C2 links would be preserved.
I wouldn’t do this to preserve links, so much as to preserve links that PEOPLE follow. But with anything but a small site, this is a huge amount of work.
For me, though, I see value in doing this, but I wouldn’t be doing it to escape the wild animals…
In short, given the links issue and the hard work for changing URLs, I wouldn’t be too quick to change. It’s uncertain what changes Google will make in the future, and you may end up doing more damage in the end.