Miguel Montesinos and Jorge Sanz from the gvSIG project have made a nice diagram showing the relationships between a bunch of GFOSS projects. It' s nice to see JTS close to the centre of the diagram - although having so many arrows pointed at it makes me a little nervous!
They show JTS having a dependency on Batik for some reason - that must be an error, there's no relationship between the two. Or does Batik use JTS?
It would have been nice to see a "parent-of" relationship between JTS and GEOS and NTS, since the latter two also form a key component of quite a few projects. And I'm pretty sure MapGuide OS uses GEOS, as does OGR.
But it's not surprising there's a few errors and omissions - it's a pretty complicated web of relationships. And this is over only what - 8 years? I wonder what the diagram will look like in another 8...