Great job, Will. It's going to be very useful in my classes.
One thing that doesn't seem to work for me is for the student to update entries. The teacher can update/delete any entry, but there are no edit/delete links for the student. I know students shouldn't be able to edit each other's entries, but the links do not show up even for own entries.
A small comment - most people will not need the "Ñ" letter. On the other hand, some languages other than English or Spanish might need other non-standard letters. The display of these letters could be language-dependent, that is, the "Ñ" would show only if the current language was Spanish, the "Ł" only if the language was Polish, etc.
Another, very minor, comment - the appearance of the entries does differ a little from the way forum posts are displayed in Moodle (it seems you were using forum posts as a model). The glossary entries do not make use of css
classes and you've used rowspan for the table cell with user picture. You can see the difference in the attached file. Of course this is a really minor thing and I'm sure you'll find more productive ways of spending time than fixing this
And finally, a feature request - Andrew Redkin mentioned (somewhere else in this thread) the possibility to link from resources to glossary entries. I've used this feature in WebCT, and I think it would be great to have it in Moodle. Whenever a text/wiki/html resource is added Moodle could search the resource text for words which appear in the glossary and (optionally) link from these words to the entries. The entries could then be displayed to the student in e.g. pop-up window. Additionally, there could be a possibility to link to glossary entries manually, which would be useful in cases when the glossary entry is not exactly the same as the word in the resource text. You might, for example, want to link from word "broken" to the glossary entry "break". I realise this feature would require quite a lot of work, but you did ask for comments and suggestions, didn't you?
Once again, thank you for this great module