Blender Git Commit Log

Node socket selection feature reimplemented from 2.49. Sockets can be selected as a sub-selection of nodes and are then preferred by the auto-connect operator. This makes it easier to create precise links over long distances as an alternative to the click & hold operator.
Socket selection is indicated by a simple white highlight circle.

Multiple inputs can be selected by holding SHIFTKEY (just like regular node select). Only one output socket can be selected at a time for each node, but several outputs in different nodes are allowed.

The auto-connect operator will prefer selected sockets on nodes for creating links. If either the output or input side have no selected sockets it will fall back to the previous behavior of chosing 'best' sockets first (colors, then vectors, then values). This could be improved in the future, but is out of scope here.