The Remote Disk function of MacBook Air works quite well, but not all of us have the external SuperDrive, nor another computer with optical drive and 802.11n, so the function might not be terrifically fast for you. Whenever I buy a new computer, the first thing I do is create disk images of the restore disks, and keep these in my backup system for safe keeping.
Once you’ve imaged your install disks using Disk Utility, mount Disk 1 on the remote computer. Next, connect an ordinary ethernet cable from the remote computer to the MacBook Air using the USB to Ethernet adapter), and then proceed normally with the system installation per http://docs.info.apple.com/article.html?artnum=307242..
This method removes two bottlenecks from the process: the remote computer’s optical drive is nowhere near as fast as its hard drive, and ethernet is vastly faster than even 802.11n wireless.
I suggest MacBook Air owners go for the USB to Ethernet adapter. In addition to speeding up reinstalls, it also dramatically speeds up the Migration Assistant and large network transfers.