Well, judging by other wikis as well as this forum, the preferable method of managing spam seems to be authenticated users' edits. Arguably, with a growing interest in the arm-specific linux development community involvement should be on the rise as well, as evidenced by this very thread. Ultimately, however, the only way to gauge the preferable method of controlling wiki edits and potential spam content is on a "live" system; so, the first step is to get it up and going, and then curate, edit, etc.
It could/should follow the same template as the ArchWiki, imho, for the sake of potential future "changes" in the project's status vis-a-vis ArchLinux proper; and, because the ArchWiki seems more organized and "contemporary" than some other popular and/or linux wikis. Based on the current similarities of the UI of archlinuxarm.org and archlinux.org I'm assuming that would be the general consensus among the leadership of the project. Therefore, some of the foundational work could be adapted from the ArchWiki itself, moving the arm-specific content from there to ALARMWiki; thereby helping to clean up ArchWiki in the process.