Yesterday I was reminded again of the difference between developing Gamebryo as a product and typical studio internal tech.
Joel, over at Insomniac, mentioned how much he enjoyed only working on one platform, and only supporting one version of Maya. While Gamebryo supports several versions each of Maya, Max, and XSI. We cover Win32 with 2 compilers / 2 versions of DirectX / static & DLL configs, Xbox360, PlayStation 3, and Wii. And, for good measure, we keep some of the code running on Linux.
David Boss also happened to have just given an update on our build system. He's running continuous integration on all platforms with unit tests; a full build; extensive regression tests; and packaging into DVD images. This turns over every night. That's impressive for an engine, tool set, and art library this size!