First, it's scalable to a real DB incredibly easily because your code, except for one line in the connection routine is compatible with any DBD::*. So if you upgrade to mysql for example, you just move the data to the db, change how you connect and your code works.

Also, all your DB calls are in SQL, which is fairly standard especially for simple stuff and allows you not to worry about the order of the file or the fields, just make your query.

Finally, the DB can still be edited, uploaded or created by hand and work with your cgi scripts.

Again, I took a fairly quick glance at your code, so forgive me if I missed something, I just thought this might interest you.