Thanks for all the feedback about this specification. I'm collecting the information to improve my blueprint http://wiki.inkscape.org/wiki/index.php/Image_properties_dialog_enhancements
Feel free to modify it adding things that I missed. Please keep in mind that the original proposal is to improve the usability of the current image properties dialog, not to provide a complete media manager (there are two extra specifications for that already started). I tried to keep things simple, modifying something that already exist in order to solve some common problems. I'm sure there is a lot of people who is, like me, comfortable with the current behavior of linked/embedded images, and would like just to have a handy way to re-link images or solve broken links easily. It also looks as a solution feasible in short term, being less ambitious than a complete media manager for all the data collection.
In my honest oppinion, I'd prefer to have a decent solution for the next version instead of having to endure the current behavior for the next two or three versions waiting for the allmighty media manager. There are lots of minor details that keep being postponed waiting for the next great refactor, but meanwhile mean a hit in usability that can be really dissapointing for regular users. Inkscape 0.47 is great and I love the new features, but there are still minor things that turn into a big headache in everyday use (being unable to choose another type units than pixels, the recent regression in the selection area of clipped objects are clear examples of that). Among those things, the lack of a simple "browse" button in the image properties dialog seems a simple change that would make everyday use much easier. I'm not against big features at all, but maybe it's not the best thing if we define an ambitious, gigantic blueprint for each minor usability fix that comes up. A less pretentious solution could drag the attention of a group of students, like Steren's for instance. An ambitious specification would bump with the usual lack of developers and keep resting as a future project for a long time.
Please take this as a constructive criticism and not as an attack to the decisions that inkscape developers have taken. Unfortunatly I'm not able to contribute with code and I can't fix things myself.
Gez