Long time Inkscape fan
The latest version 0.91 is the result of a four year bug hunt and conversion from C to C++, any new functionality was all linked to that effort and the result is nothing short of amazing. Try find other software that managed to increase its functionality in such a period. And this was all done by volunteers, rather than day job programmers. Respect where respect is due.
The last stable version was 0.48 and the version 0.91 was chosen to reflect the amount of finish this latest version has to come near the 1.0 mark. Officially it is still a Beta, but as many users can contest to the quality of this Beta is such that is is fully functional and usable in a production setting.
Though Inkscape is very good for web design, when it comes to print, there are some serious problems to overcome yet. CMYK is still marginally supported and you'll have to use Scribus (which was missing in the review) to print to press. Scribus however doesn't support SVG filters, so a lot of detail is lost in translation and most work will have to be converted to Bitmap to make it print the way you designed. Kind of a preprocess RIP which in these days of big harddisk isn't the greatest issue, but still an annoying extra step in the work flow.
True,.. if you come from an Adobe background, you'll really have to get used to the interface which wouldn't be a problem for Coreldraw users.Methods were much more like the latter than Illustrator, which I always found to be a gruel to work with anyway. In general though, once you get the hang of the quirks that Inkscape has, you'll find your production speed increase with some 25% compared to Illustrator, just because the functions are more logical and easy to access. Unless you hit big files with tonnes of nodes that is. Inkscape still lags on the memory management.
That the GIMP forces you to export work to my idea is very good, though I wonder if they shouldn't have you let safe a copy a XCF at the same time to prevent people from their own stupidity. To my idea if you safe work into a lossy format it should be an export and not like Adobe does lard it with metadata to make it functional in their Suite apps. A discussion on this issue is ongoing in the Inkscape developers channel and word is not out yet.
For anyone with an interest in using FOSS software alternatives in graphics design, I can recommend using Inkscape (vector), Gimp (bitmap), Libreoffice (Draw has very good PDF import and SVG export of that, with SVG font support, though that sadly is deprecated in SVG 2.0), Scribus (Indesign alternative), Blender (for your 3d objects and video editing).
All in all though, Inkscape surely can be considered a serious alternative for 80% of the work done in Illustrator for an unbeatable price. And it works on Windows, MacOS and Linux.