allow file folders

Some bibliography software packages offer the option of setting up user defined file folders so that references can be sorted based on subject area and sub-area (or in any hierarchical  fashion that the user prefers).  This allows a level of organization not supported by a simple keyword search because it allows the user (not the software or text content of the reference) to define what is considered related.  For example one reference may be deemed “related” only in that it describes a method that the user thinks may be applied to a totally different subject area.  

Will Endnote ever give users the capability to do this?  Maybe more importantly, is this something that anyone besides me would be interested in? 

There are the groups and subgroups, and records can be assigned to multiple subgroups?  Doesn’t this achieve your “wish”?

Well no not really, because that only allows two levels of characterization and most detailed scientific findings (and published reports of them) can be more accurately filed (and retrieved) using multiple levels.  For example this might be a series of folders that I would use:  Medical - Diagnostic - Radiology - MRI - contrast agents - iron oxidies - USPIOs- USPIOs for lymph node imaging.  Just within the final catagory there are hundereds of publications.   Biblioscape is a program that will do this nicely but it needs to be run on a windows virtual machine on a Mac and this sometimes creates some gliches.  

I cannot agree more. At least 3 levels of subgroups should be allowed, and this is the one main reason I’m having doubt to completely switching to EndNote for organizing my papers.

Absolutely. I fully agree!!!