With 0.8.1 the Wesnoth dekstop file ends up in /usr/share/games/applications and not /usr/share/applications and is not found by Gnome. In addition, KDE now looks in /usr/share/applications so there is no need for a special KDE .desktop file. Reproducible: Always Steps to Reproduce:
eeeew. That's because you don't have gnome-libs installed and the autoconf stuff in wesnoth is ugly.
I guess it is. But gnome-libs, what about them?
The configure script checks for gnome-config to see if it should install gnome1-style desktop files or gnome2-style desktop files. I've emailed upstream to see if I can get them to fix up the desktop stuff for the next release. If you would like to have a nice clicky icon before then, you can merge gnome-libs and remerge wesnoth.
Great! Na, I just moved it from games/applications/ to applications/.
Upstream knows about the issue and is working on it. If the 0.8.3 release hadn't been so messed up WRT the desktop files it probably would have been fixed in that release. Probably will be fixed in 0.8.4.