I've just been trying out the Linux port of Xara Xtreme, the professional vector graphics program recently GPLed by Xara, and it has very quickly become my favourite graphics editor, even though it still has some major major bugs (porting bugs, obviously).
It's much more feature-complete than Inkscape, probably because of its history as a commercial program. I really can't imagine doing some of the things given as examples (e.g. a nearly photo-realistic cross-section of a car, with nearly everything modelled in) in Inkscape or any of the other vector editors for Linux.
With Xara you can literally create all sorts of things, e.g gel buttons for websites, company logos, etc. from scratch in less than 10 minutes. It's a great project with a lot of potential for Linux-using graphic artists (people unlike me.) My only major problems at the moment are the instability (which will hopefully clear up within a few weeks) and the lack of SVG support, which is a big problem if you want to interoperate with other programs. The one major feature it misses at the moment is a colour editor, although the developers say that will be there given a few weeks in the next recommended build.
You can download Xara Xtreme LX from http://xaraxtreme.org.