Correct me if I'm wrong, but skimming the roadmap I was unable to find any reference to work on a swatch palette for named colors, grdients and patterns.
I'm talking about a single dialog where the user can create named colors which would later be referenced by name in the XML (I don't know if SVG allows it) - for example, suppose I create buttons and other graphic elements for a website design. I have many of them and they are differently shaped. I might want to paint them with a blue color. I then create a new swatch, name it "buttonBackground" and set all the background rectangles to use it. Later, I may want to change the entire color scheme of the website - in this case all I need to do is just access that swatch and change its value to, say, red - and all The button backgrounds immediately update.
I feel this is a very basic, important feature missing from Inkscape. I know from experience I use this extensively on other applications, and even on Inkscape I try to fake this feature by creating gradients with two identical colors and sharing them between shapes (but it's awkward and the gradients can't be named and are hard to find among the long list of used gradients in a large document).