"1: Will that proprietary, mission-critical application run on
the new platform?
"One of the first things I tell people who are considering a
migration is that, yes, most likely there is a Linux equivalent to
the application you use. Photoshop? Gimp. Adobe Reader? Scribus.
But there are certain instances where an application has been
written specifically for a purpose (or company) and does not have a
cross-platform equivalent. In this case, I would say you could try
running your application with Wine or you could run a virtual
instance of Windows to get that app running. But this takes time
and effort and, in some cases, isn’t as stable as one would
like (especially in the case of Wine)."