http://www.inkscape.org/screenshots/gallery/inkscape-0.44-nodesculpting.png
An entirely new way of manipulating paths in Node tool is added in this version: Node sculpting. Normally, when you have several nodes selected and you drag one of them, all selected nodes move by the same amount. Now, if you Alt-drag one of the selected nodes, only that node is fully displaced; other selected nodes are moved less than the full amount, so that those farthest from the drag point remain stationary.
So, for example, if you select several nodes on a straight line and Alt+drag the middle selected node, the path will bend into a smooth bell-like curve. Nodes' handles are also adjusted correspondingly to keep the overall shape smooth and natural. (If you don't have enough nodes on a path fragment that you want to reshape in this way, just select the end nodes of that fragment and press Ins a few times to populate it with nodes.)
Moreover, node sculpting is sensitive to pressure of your tablet pen. If you press slightly, your curve will have a narrow sharp tip (i.e. the nearest neighbors of your dragged node will move only a bit); if you press hard, the curve's tip will be wide and blunt (i.e. the nearest neighbors will move almost as much as the dragged node). (Hint: to stop dragging without losing your shape, first release Alt and then lift the tip of the pen.)
There are many possible applications of the sculpting technique. To take a simple example, selecting all nodes of an ellipse-like shape and Alt+dragging one of them will smoothly and naturally stretch and skew the entire shape in any direction. Doing the same to a complex path, such as star or spiral, will twist and punch it without destroying its intricate structure - this is the way to get squashed or self-intersecting stars, eccentric spirals and other shapes not easily doable before. Selecting only part of all nodes allows you to smoothly reshape parts of the figure without disturbing the rest.
Especially useful node sculpting is for complex natural paths, such as calligraphic strokes or bitmap traces, where you often want to do large-scale pushes and bends without destroying the small-scale features. Things like making a calligraphic stroke narrower in one place and wider in another, or extending the ear or flattening the nose of a head, or any other reshaping of complex paths - all this is now much faster and more natural to do using sculpting. Starting from en ellipse with added nodes, it takes just a few Alt+drags to tweak it into a silhouette of a head, or a map of Australia, or an Inkscape logo!