My new word is "operational". I use it when alerting people that a new development feature is in place:

This is operational now.

I use this word to cover my ass. "Operational" means the feature can be used, but it hasn't necessarily been verified to function under all circumstances. In other words, there could still be bugs. I haven't tested every possible angle of the application.

In a sense, "operational" means "beta."

Web applications are tricky to get right. Someone always finds a hole or bug that may not have been evident to you during the development process. This is especially true if you're the lone developer of a particular project, and you (as a single person who probably doesn't actually use the app) can't possibly consider (or simply remember!) every angle of functionality that a "seasoned user" would know.

Here are a couple of things to remember:

1. How are users getting to the application? There could be many pages that let them enter into your page, each with different criteria. If you're not aware of all of the entry points, don't manipulate the database structure, or otherwise lock users out.

2. Consider the least likely thing your users will do within your application. You can bet they will do it. In a sense, you have to protect against every possible action, even actions that may seem stupid to you as a user. Remember, users are not you. They will always do unpredictable and unanticipated things.