A couple of searches are giving me strange results:

jempeg.soup.5.name=Orphaned items
jempeg.soup.5.externalForm=search:(refs \= "0")
jempeg.soup.6.name=Items with optional features
jempeg.soup.6.externalForm=search:(((options like "x") or (options > "0")) and (not (options \= "0x0")))

"Orphaned Items" contains about a fifth of my tunes, but they all have refs between 2 and 13, not zero. I believe it should be empty. (Hmm, what runes do I need to get my All Tunes soup back? Search on (type="tune"), perhaps?)

"Items with optional features" is empty, even though I can see a handful of playlists with non-zero options.

The following two searches work fine:

jempeg.soup.7.name=Marked tunes
jempeg.soup.7.externalForm=search:((marked like "yes") and (type \= "tune"))
jempeg.soup.8.name=Fixed-rate tunes
jempeg.soup.8.externalForm=search:((bitrate like "fs") and (type \= "tune"))