Support

Of course, it's in the download page. Look at the bottom, below the installable ZIP archives.

The HTML version is very readable at its current width of maximum 900px. I have tried on my iPhone, iPad, HTC Desire, MacBook Pro 13", Apple LED Cinema Display (27"), HP Pavillion (15.5" WXGA), Samsung external LCD display (19"), EIZO 17" CRT display, white-lable MSI laptop from back in 2005 (15.3" WXGA), Asus EeePC 901 (9") and Asus Aspire One (10"). Phew! That was a big list. In all cases I use factory defaults and 100% zoom level. Obviously, if you set the zoom level to 75% or, worse, 50% you get too wide sentences which are impossible to read. Same goes if you set the monitor's DPI wrong. The way it's set up right now, the text should appear about the same size as most novels on all displays except the mobile devices (it appears about 50% as big). At 600px wide the text is unreadable as the sentences are way too sort :)

Ah, I see your point of view. There are two popular ways to typeset text: three columns to an A4 page or a single column. The former is used in magazines and newspapers (albeit the newspaper is usually A3 format), the latter is used in novels and technical documentation. That's why it's typeset like that. The PDF is also typeset the same way. They actually come from the same DocBook XML source and the same XSLT conversion stylesheets. Well, if the PDF is more convenient for you, no problem :)