While it does mention the locale.gen method, the quick install guide still mentions the userlocales method as the primary method for changing locales. I would suggest this be demoted and the locale.gen method made more prominent, or remove the old method altogether as it appears to be confusing some users. I realise that it's the users fault for not reading the guide fully, but it is supposed to be the "quick install" guide and as such I think you should be able to just skim through it.
The guide needs a few other updates as well; I'll handle this.
Thanks for reporting, fixed in CVS. Removed userlocales entirely, and made several other updates to the guide. Still TODO: s/2006.1/2007.0 for the new release, once it happens.