brain is changing, and some ramifications that might have for preaching. You might remember that within the brain are neural pathways that connect your brain cells together so that you can think something or do something. The more often you think or do something, the larger and stronger that pathway becomes. This is the physiological root of habits and skills.
But the same phenomenon happens in churches. The more we think or do something the easier it is to continue to think and do the same things. This is, in part, due to the combined neural pathways of all the people involved. Basically, the less a church changes, the harder it will be for a church to change.
This is why emerging leaders often don't have a place to serve - it's easier to ask the same people to do the same things again. This is why the carpet is still from 1984, it's easier to just leave it the way it is.
Is this why you aren't using PowerPoint when you preach? Is it just easier to avoid change?