I think there are 4 communities that visit and use this board.
1. Interested in the technology, may send designs to a print agency such as Shapeways.
2. Bought a pre-built printer and have no desire to get into the nuts, bolts, gears and electronics of it all or use a printer owned by their employer and want to improve the output.
3. Bought a kit or a pre-built but are obsessed with how it all works, improving the printer's capabilities and their own skills and knowledge. (Me)
4. Hard-core built a printer from scratch or are building a printer out of parts from multiple vendors.