I believe this is targeted at system administrators, and not the average desktop user.
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Edit: as a regular user of Screen, I cannot pass up an opportunity to promote it. It is most definitely one of the most amazing pieces of software I've ever used, CLI or not. The ability to run multiple terminals inside a persistent session is enormously useful.
I not only use it for software development (where split-screening the Screen session gives me the best development environment I've ever used) but also for running all kind of other applications. I use rTorrent (http://libtorrent.rakshasa.no/), Irssi (http://irssi.org/), ncmpc++ (http://unkart.ovh.org/ncmpcpp/) with MPD, and CenterIM (http://www.centerim.org/), all in a Screen session on my always-on desktop, which lets me turn off my laptop whenever I want without closing any of those applications.