Is your application open source? If so, I wouldn't worry about packaging for every distro. Just make sure that your application isn't difficult to build, and

Is your application open source? If so, I wouldn't worry about packaging for every distro. Just make sure that your application isn't difficult to build, and most things (paths, etc.) are configurable. The config path can be handled with a command line switch. Once you've gotten your application so that it can be built easily, I'd only really worry about packaging it for your distro of choice. If people are interested in your application, it'll get packaged for their distros. If your application is proprietary, I wouldn't even worry about packaging it yet. Getting most Linux users on non-essential proprietary software will be an uphill battle.