Well, I write about my research in musicology. Usually it is about lute music from the 16th and 17th century. In those days they used various types of tablature notations with various symbols. This is very specialised stuff so you can't even write that music 100% correctly with apps like Finale or Sibelius. There are some apps (most of them Windows only) which were written especially for that, and which contain specially designed fonts.
Now, when you need some of these signs in a (explanatory) text, you take them from one of these lute-specific fonts – it should be the exact same you've used for the musical examples. For that you had glyph view in the old Character Viewer. In (Mountain) Lion's "Special Characters" app you have a similar kind of view which allows you to use those signs: For most fonts you'll find them under "Dingbats", where you can see the Dingbats by font name. However there are fonts which the Mac just doesn't list under Dingbats, and for those you'd still would need glyph view.
It could well be that it's just a problem because the fonts are not coded in the right way, I am no computer expert. But in the old Character viewer app you could just have all available signs of a font listed and selectable (and insert by double-click) in one place, that was very handy.
Of course I don't expect these symbols as being supported, because so few people really need them. However, before Lion it was nice, the Mac was a bit more versatile in that regard – especially for users like me (and most of my colleagues) who don't even really know what "code points" mean (you mean the unicode numbers?)
See enclosed pic with signs I need nearly daily. However these I could find under Dingbats in that particular font. There are others, like various signs for embellishments which fell out of fashion during the last few centuries…
However, even for quite simple standard stuff it would be useful to have glyph view. As an example, if you want to print a CD-label or booklet, you need those little numbers in boxes, for the tracks. Haven't found those in any code table. Now, there is a font of course, at http://www.fontspace.com/fontgrube/cd-numbers. Since it doesn't seem to work to enter the signs by keyboard (it works on Windows however), glyph view would come in very handy. You can list all numbers in Fontbook, however you can't select all of them, because depending on which view option you take, you can either see all of the signs or you're only able to select of a few (unluckily exactly the non-serif are missing there). I believe part of the problem here is that the cd-numbers is a TTF. Using the app Glyph mini I've converted them into Open Type and now one can select them in Fontbook. However: is there any easier way to get such numbers in boxes? It would be very cool if we could have them not only in one font but in various fonts (not only serif and sans serif).
Anyway, here my lute signs:
Best wishes…
