Hi,
I have two points with this new tool:
1) It is misleading to call the tool "flood fill", because it doesn't fill something with a color but creates a new object. We could call it "Create by color" or perhaps someone has a really good name. ;)
2) In the "Fuzzy Selection Tool" in Gimp I can control the threshold of similarity by dragging the mouse downward or to the right: the farther I drag it, the larger the selected region. And I can reduce the selection by dragging upwards or to the left. That is really helpful, so I don't need to click, undo, change threshold, click again, undo ... It would be very useful to control the tolerance in Inkscape the same way. 2a) Perhaps you can even rename tolerance to threshold so Inkscape and Gimp have the same wording.
Regards, Tobias