Update 2010-05-02: See this comment.
I read an article in the Dec 2009 issue of Linux Magazine, one of several Linux-focused magazines we get at the office. I’d like to link directly to it, but it the magazine’s own website doesn’t offer the article or even a reliable permanent link to the issue number. Hint: hey guys, sort that out.
The article was about configuring ACPI hotkeys to support your specific laptop. IE, the buttons for “sleep”, “brightness up”, etc. For most laptops this already works on Ubuntu. On my Dell Vostro 1500, every button except for “sleep” worked right after install. This is Linux, so there is always some way to fix that.