... Because this would be Essential functionality for many applications. For instance, imagine a relationship database where you only want to see 2-chains distance from the center. Search for a node... and then imagine drag+drop onto the selected node to establish an edge between them! Super cool.
Also, in a community respect (since I'm a community organizer), you could do cool things like...
* search for all nodes (people,organizations,donors, whatever) with similar interests.
* compare needs/asset lists...
Imagine being able to say, "show me all the folks within three chains of me OR who live in the same town who's 'I'd like to learn..." list scores high compared with me "I can teach/have these skills" list.
But step one, to me, is taking in GXL, and being able to save in that format. See "Future developments" for a post on that.