in reply to Porting to mod_perl questions

  1. No - if your web application is running quickly under a realistic load, then you don't need mod_perl.
  2. For parsing cookies, CGI.pm can still be used under Apache::Registry, or you can use the much faster Apache::Cookie.
  3. If you use CGI::Application to build your web app, it will be trivial to port it to Apache::Registry, should you reach a point where mod_cgi is no longer fast enough.
:-)

In Section Seekers of Perl Wisdom