For players, this version adds support for drag&drop station construction, connecting channels between various companies, and other minor upgrades and fixes. The big news, though, is support for scripted scenarios! This promises an entirely new experience for single player mode…
Apart from these, a somewhat hidden feature is that dedicated servers now do not load image data. Thus, they need drastically less memory.
You can find a full changelog and download links for windows, linux, haiku and mac binaries at the International Simutrans Forum.