Very nice, I am just missing some references to some of your claims, for example that 65-90 characters is the perfect width .
I can of course google it and find it but I think it would still be good to include it on the site.
It's not a scientific number by any means, rather a general "consensus" derived from all the typography literature and articles I've read. The measure is not as simple as it seems, though; Readers seem to prefer a shorter measure while reading speed is actually increased with a longer measure, like shown in this study:
http://psychology.wichita.edu/surl/usabilitynews/72/LineLeng...