How experienced is your audience in the technology presented in your talk? What's your talk on?

Less experienced: I would go with a step-by-step walkthrough of a basic example, with some "Going Forward" inspiration at the end.

More experienced: I suggest doing a deep-dive into an aspect of the technology that may be taken for granted. A lower level understanding is usually appreciated. Maybe address some newer features that can improve a developer's workflow with the technology.