I'm new here and I'd like to wish you best of luck with InkScape, it really sounds like a good idea.
Firstly congratulations on choosing a name I can immediately pronounce, that is not an acronym, that I'm not embarassed to admit I use or say out loud and that does not feature an over abundance of G, Q, or K that seem to plague so many other projects (I'm sure you all can guess the ones I'm talking about).
I found out about Inkscape from a story on Gnomedesktop.org which from the various posts I'm sure you are well aware of but I think it might be worth linking from your news page (and this mail did invite suggestions http://sourceforge.net/mailarchive/forum.php?thread_id=3434272&forum_id=... ) I'm also having minor difficulty downloading this file, I only get the top chunk http://www.inkscape.org/mockups/export_dialog_02.png
Which leads me to my next point, the Export Dialog. Rather than make specific criticism of each approach I would put it to you that it would be best to use a standard Save Dialog with an additional "Options..." Button. The Options button would prompt uses to change the export settings, these should probably also be available through some sort of Import/Export preferences dialog. Why do it this way? Other programs do it this way but more importantly that that I can promise you that users will not want to change the export settings each and every time, and being able to set them once (or just once for the current session or project) and keep reusing the same settings until you feel the need to change them and keep them out of your way. (This is an approach I have been advocating quite strongly on the Gnome usability list mailto:usability@...45... so that when the GTK File Open Save As dialog gets redesigned that developers will have a clear and standard way to extend it rather than cluttering the dialog with all manner of new features.)
The website says "We aim for capabilities similar to Illustrator, CorelDraw, Visio, etc." I hope you will also aim for a user interface similar to those programs, except of course when there is a clearly better alternative. You'd be amazed how lost I feel in Sodipodi as it does(/did) not have a menubar or document toolbars. Keeping the interfaces similar makes it much easier to reuse existing books tutorials and other resources already targeting the dominant software and also helps kill off the distasteful "marketable skills in the workplace" crap that I'm forced to admit happens all too often.
I'm a fan of portable cross platform software - who know what Operating System we'll be running in 5 years, but I'd like to still be able to use my favourite software - but at the same time I encourage you to not just get involved with Gnome and try to follow the Gnome Human Interface Guidelines (HIG) where you think it is appropriate but also help push for changes and more flexability where you really dont think the Guidelines are appropriate.
I wish you the very best of luck with InkScape and I hope you can make the most of its potential and satisfy so many potential users out there.
Sincerely
Alan Horkan http://advogato.org/person/AlanHorkan/
PS I've subscribed to the list digest so that I can lurk and I'm fairly busy at the moment, but if you would like me to try and respond more promptly please CC me in your replies.