Perhaps, having had Macs for nearly 5 years that have lacked Ethernet ports, I'm less sensitive to that. I'm just glad that a) Apple finally made good use of the Thunderbolt port in something that doesn't cost $1000, and b) the adapter is gigabit, compared to the 10/100Mbps port that I was using previously (in a pinch when I actually needed Ethernet on the Air).
Ethernet comes in handy most often in an office, where for security and cost reasons most companies still prefer hardwired solutions. That said, an office is also more likely to use a desktop, or a dock of some kind. I'm a bit surprised no one else has come out with Thunderbolt-compatible displays yet. Intel should get its act together on promoting the port.