I have done a quick spike at building proper install and upgrade instructions for the current HEAD, which will soon become 0.2. Those are simple text files now part of the hostmaster install profile named (unsurprisingly) INSTALL.txt and UPGRADE.txt. This in turn deprecates the current install instructions which are relevant only for 0.1 and will be removed from the wiki when 0.2 is released. The rationale behind this move is that it was becoming too complicated to maintain multiple versions of the same document in the wiki.. Besides, much of that documentation was duplicating the help already provided by the Hosting wizard.
If there are any issues with the documentation, reopen the install or upgrade issues. If they do not pertain directly to the install or upgrade instructions just open a new issue in the Hostmaster project.
Yes, this means I have been able to install HEAD and provision Drupals using what will be the next release. :) I haven't tried using the upgrade instructions however, so I welcome feedback on those.