If you've been trying to figure out the usefulness of the patterns over on phpPatterns.com, then this new piece from DevArticles might give you the intro you need.

In Introduction to Design Patterns Using PHP, the author tells you what design patterns are and aren't, and why they can be useful to you and your code. They give you some examples, and some "what to look out for" tips near the end. These can help you keep from doing things like over using the patterns, or over designing your applications.

Patterns can help not only to make your code cleaner and easier to maintain in the long run, but they can also help make things a bit more standard around the PHP world. Just be sure you really need to use a pattern in your app - there's no use in using something you don't need.