Not necessarily true or they would have stopped shipping things like the terminal.app a long time ago (or including python, ruby, etc.). Even apps like Automator are probably out of the scope of 'laymen'.

I only use it as a cheap way to mentally background apps that won't be looked at as often (e.g. iTunes, running a server in Terminal).

I find that the focus model tends to break down in Spaces for any multi-window application like Finder, Chrome, Emacs and Terminal. If every window of an application is going to jump to the top then that just adds extra work to switching desktops.

That being said, I do like the Application->Window switching model on it's own and wouldn't trade this for Virtual Desktops.

I'm not sure where I stand on this, however, I'd like to provide one data point, one that I expect many HNers share. I'm primarily a web developer, though I do frequently work on Android projects or random hacking on some python projects ( sage anyone? ). For web development, I find spaces essential. I have several api docs open at any given time, eclipse for android stuff, Aquamacs ( emacs in cocoa ), potentially an Android emulator, a preview image from our designer, several browser tabs for email, roadmap, and backlog tasks and a team chat window.

I, too, thought that most people wouldn't really care much for spaces, however I have noticed several of my non-technical friends using and began wondering. The conclusion that I came to is that, if you replace my IDE with something like MS Word and my text editor with something else, perhaps Photoshop or Illustrator, you'd get roughly the same workflow that I have, just without the code.

Now, I'm not saying that Spaces is essential, but I this is one case where something we think is nerdy, is actually pretty main stream.

Since were on the topic of application visibility and switching. I'm wondering if there is a better way than spaces. It's obvious that full-screen mode with easy switching isn't it. I find that context switch to complicated though I'm not quite sure why - way back when I was on windows, that was the way I did things. Perhaps expose is underused?