Another cheaper vector drawing program worth looking at is Serif Drawplus (circa $100 US for the latest version, less down to free if you buy earlier versions)- if you look at RobA's sticky on different software that's available you can find more information there. Still...inkscape is free and pretty good too from what I've heard.
The best thing about Drawplus is that the learning curve is really quick which makes it a joy to use. Everything is intuitive.
The latest version of inkscape has implemented svg filters, as well, so a whole host of effects can be acheived (who the UI is a bit awkward, imoo). Here is an example tutorial making a logo:
I use both, but almost always use Illustrator for maps. The "high quality at every scale" and "ability to move lines long after I drew them" wins for maps, as far as I'm concerned. It is true, however, that using vector art does lend a particular "look" to your maps, and that can either work for or against you.
As for "worth the upgrade", I can only speak for the Mac version. The CS3 version was very much worth the upgrade, because it was Intel native. Feature-wise, it didn't seem much different than CS2.
For those looking for cheaper alternatives for the Mac, you might be interested in my Mac shareware recommendations, particularly Pixelmator and VectorDesigner. (Inkscape on the Mac, btw, is garbage.)
Last edited by Wordman; 04-24-2008 at 02:28 PM.