Information design is primarily concerned with organizing data into structures so as to maximize ease of access to/use of the data. The fact that there is a Chatterbox, Epicenter, Vitals, New Writeups, etc. visible on your screen right now is information design -- if each new addition to E2 was placed right after the last one, and writeups were not organized by node title, well, you can imagine how much time we'd want to spend here. And the order in which you have those items set up is information design, too (as well as being among E2's best features, IMHO).