As previously mentioned, the not-quite-freeness of the old AT&T license kept Xgobi and Ggobi in non-free, and Rggobi contrib. Thanks to a recent license change (mirroring the earlier switch of Graphviz) to the Common Public License, Ggobi (and thus also Rggobi) are now suitable for main -- and included as of last weekend thanks to the swift work of the ftpmasters.
As I also finally requested the removal of xgobi, which was also promptly executed by the archive maintainers, all of my packages are now in main only -- for the first time since I started to contribute to Debian close to ten years ago.