Dartmouth College has put out a really interesting technical report about the way that use of their 802.11 Wi-Fi network has changed over time.
Part of their abstract:
We employ several measurement techniques, including syslogs, telephone records, SNMP polling and tcpdump packet sniffing. This is the largest WLAN study to date, and the first to look at a large, mature WLAN and consider geographic mobility. We compare this trace to a trace taken after the network’s initial deployment two years ago.
The 21-page report makes good reading, and you don’t need a PhD in computer science to understand it. Highly recommended!