That's not necessarily true. My main client is a small office with a lot of overworked people light on technical know-how, with a few policies set in place by management with similar workload and technical know-how. The average user here has dual 22" monitors, and a standard workload consists of 7-10 Excel spreadsheets open at once, stupid-sized Outlook mailboxes, multiple web sites, PDF document viewers / editors, along with the craptastic line of business app they use based on Visual Foxpro. It's a struggle to provide them with enough I/O on the desktop to make their "work harder not smarter" brute force approach doable. This isn't even calculating in the deleterious effects of a anti-malware solution, or any sort of management suite.
1GB on Windows 7 is a recipe for disaster. I wouldn't run 1GB on a Windows XP machine, unless the user doesn't use more than one application at a time, and uses some form of webmail instead of Outlook and Exchange. Factor in a lifetime of 3 years (at least), and there's no way that you should be buying any desktop with less than 2 GB of RAM, dual cores, and some modern SATA rotating storage (not that bottom-of-the-barrel low-performance crap that gets used in cheapie desktops) if the users do more than look up YouTube videos on the Internet.