i regularly see people hovering their mice over every individual pin of a node, and i agree that this is a colossal waste of time. but this is not a problem with vvvv; everybody just keeps forgetting about herr inspektor, whose primary function is the display of ‘what they do/what they are’. the tooltips on the individual pins are for finding the pins you want to connect (and checking values/spread counts on the fly), it is not their duty to describe the node. this is why herr inspektor can be attached, while the tooltips are always dependant on mouse position, unobstructive and volatile.
i’m sorry i have to speak out so strongly(italicly), but i must avert the implementation of ‘tooltips that stay until you click somewhere else’, since they commit the primary sin: obstructing whatever lies under them and thereby removing other potentially important information from the screen which, in the actual case of vvvv, means not being able to connect anything to anything at any given time until you explicitly tell them to stop that. i don’t think there is anything worse you can do in the context of this interface.
if you really need something to pop up, use autohotkey to map ctrl to toggle between ctrl-i and ctrl-w, for example. although i would advise you to stay out of the excellently mapped lower left half of the keyboard unless you can afford to loose some of that sweet, sweet functionality ;)