Have you ever considered packaging your application into a deb package (Ubuntu) users? What about a private PPA? I'm probably asking too much and I understand your application is commercial not open source but I think you would see a huge adoption rate if it could be made available this way.
I'm not that knowlegdable of Linux but its enough of a headache maintaining Linux, Windows and Mac versions, without offering multiple Linux Distributions. But if you were interested in helping me with this then I might consider it
I wish I could. While I use these features quite a bit I don't do a lot of Linux software packaging. I'm probably just not the best person to ask for this. I'm sure it wouldn't be hard to find someone willing to do it though. However, setting up a private PPA on launchpad for a commercial project isn't free and I'm guessing it would take someone who has access to the source to do it correctly since releases are probably built from source and packaged all at the same time using something like maven or ant in conjunction with a source code management system like Subversion and perhaps a continuous build system like continuum.
I think I could try to do it.
Repository is not a very big problem, as it can requires only a ftp or http server
I don't even think, that I'd need source, as I would just tell debian/control to unpack installer (BTW. is there any way to do it switchless?).