+1 for true Boolean search functionality, i.e., AND/OR/NOT operators and the use of parentheses to define sets of data and order of operations.
Also, I've noticed that Evernote's existing AND operator (ANY:) doesn't work for different data types.
For example, "ANY: NOTEBOOK:anybook TAG:anytag" does not return any results. It seems ANY only works if what follows is a list of terms to be found within a note. If anyone has solved this, I'd love to hear from you. -Thanks