From my MIME::Lite docs:

send HOW, HOWARGS... 

Class/instance method. This is the principal method for 
sending mail, and for configuring how mail will be sent. 
As an instance method (with no arguments), sends the
message by whatever means has been set up (the default is
to use the Unix "sendmail" program). Returns whatever 
the mail-handling routine returns: this should be true on 
success, false/exception on error: 

    $msg = MIME::Lite->new(From=>...);
    $msg->send || die "you DON'T have mail!";

Of course, just because sendmail didn't error doesn't mean the mail got delivered. You could try the send_by_smtp method instead, but that's still subject to soft email bounces.