Nice one. But you need to know what you're looking for. For example:

$ perl -MCPAN -e 'CPAN::Shell -> m (shift)' DateTimeCPAN: Storable loa
+ded ok
Going to read /Users/liz/.cpan/Metadata
  Database was generated on Fri, 13 Feb 2004 01:50:02 GMT
Module id = DateTime
    DESCRIPTION  A complete, easy to use date and time object
    CPAN_USERID  DROLSKY (Dave Rolsky <autarch@urth.org>)
    CPAN_VERSION 0.20
    CPAN_FILE    D/DR/DROLSKY/DateTime-0.20.tar.gz
    DSLI_STATUS  bmpO (beta,mailing-list,perl,object-oriented)
    INST_FILE    (not installed)
[download]

is a module that I don't have installed: CPAN has 0.20. Whereas:

$ perl -MCPAN -e 'CPAN::Shell -> m (shift)' ifdef   
CPAN: Storable loaded ok
Going to read /Users/liz/.cpan/Metadata
  Database was generated on Fri, 13 Feb 2004 01:50:02 GMT
Module id = ifdef
    CPAN_USERID  ELIZABETH (Elizabeth Mattijsen <liz@dijkmat.nl>)
    CPAN_VERSION 0.03
    CPAN_FILE    E/EL/ELIZABETH/ifdef-0.03.tar.gz
    MANPAGE      ifdef - conditionally enable text as code within pod 
+sections
    INST_FILE    /usr/local/lib/perl5/site_perl/5.8.3/ifdef.pm
    INST_VERSION 0.03
[download]

shows that I have the "ifdef" module installed. Note that both the "CPAN_VERSION" as well as the "INST_VERSION" are shown now.

Liz