I am having an issue where files will simply not STAY in the spotlight index.
I use a variety of special characters in the file name, e.g. ¶, to categorize various files, and recently I realized that not all files (mostly .jpgs) are showing up in my spotlight searches. What is very strange is that other files so tagged, even in the same folder, are consistently showing up!
For your further weirdness enjoyment, if I reindex spotlight on the directory, the missing files will then show up in a search done immediately afterwards, but then disappear once more! The same files keep dropping out, and they do so within minutes after performing the reindex.
I have tried duplicating the folder, and deleting the original. This gives the same behavior: the items will show up briefly, then disappear again.
This happens all over the place on the disk, and on more than one hard disk. I have also even done an erase and install on the system (a different issue), and this behavior still remains.