[eluser]brianw1975[/eluser]
There are several reasons to start moving it over to CI
a)It's already up and running! Just take working code and break it down into objects - this also will help your understanding of the project and will grow your abilities to recognize needs and requirements of projects.
2)It's a fantastic learning experience and by doing it you will improve your abilities and thus decrease your needed time in the future to make additions/changes/upgrades to that site.
tres)A basic requirement listed in most job ads is OOP PHP 5.2+
d)Since the site is already running, converting to CI doesn't have to be top priority.
5)With knowledge of OOP PHP methods, structures, DRY (don't repeat yourself) ideas it will give you a solid foundation for moving to AGILE programming through either Scrum, XP, TDD (Test Driven Development), etc, knowing those things increase your base salary as well (especially in places that don't already do that but are looking to do that)
Of course, all of the above assumes that the app is already up and running. Personally, I hate the procedural based site I am helping to debug/upgrade/modify... I want to strangle the programmer.
Anyways, loads of reasons to move to anything that is Object based