[Hellmark]

It really wouldn't take much for them to make a version of Kindle 4 PC for Linux. Heck, Wine allows for compiling windows apps with linux support, so it would appear to be a linux native app.

As far as requiring different versions for different distros, not necessarily true. It is very possible to make apps for linux that will work the same across multiple distros. The biggest thing to allow for that is to statically link the libraries. Usually where issues come in, is where the app is dynamically linked, and is expecting a certain version of a library at a specific location, and it isnt there or is a different version. If you statically link, the libraries needed are compiled into the same file, with the end result is an app that will run the same on different machines, but be a bit bigger.