workflow headers not clearly shown
The overall layout of the mercurial.selenic.com pages is very clear for reading. So I like it. But I noticed on he Guide page that the titles of the different workflows have the same size and emphasis as the subsecuitn in each workflow. F.i. there is the group title "Basic workflows", and then the first workflow "Log keeping", followed by the subsection "Use case". I think the "Log keeping" header should have a size/emphasis that is between that of "Basic workflows" and "Use case", but now it is the same as "Use case", which does not show it clearly as a higher level. That would even improve your already fine layout, I think.