Many of the people here are already also on the MobileRead forums, so you're not likely to lose too many of the associations found here. "Golden update" files have been archived by users on both sites, and could be exposed on the web in response to a request there, so you're not going to lose access to Entourage-specific files even if Entourage disappears.

As for backing this forum up, that's problematic. If you have a paid version of Acrobat, you could create a PDF from this website and just start clicking on every thread, pulling the content into the PDF file, but that would be pretty tedious! I'd suggest printing to PDF, but that also requires opening each thread. Maybe someone at Entourage will make the source database available someday?

Many issues you face will be Android-centric, and answerable through any one of the other website/forums.