I was on Vision magazine's website and found an article by Greg Atkinson called "Less Is More". Here is some of key thoughts/ideas that you should take from the article:

"Although their presentation software has the ability to put text over moving/looping backgrounds, they used mostly still backgrounds. Often when a church moves from PowerPoint to a presentation software designed for worship they forget about still backgrounds."
Use More Still Images:
I remember using a moving background at a small gathering behind the song text and noticed that people were developing vertigo halfway through the song. So, be cautious of using moving backgrounds too often. I even suggest using white text over black-background often. It allows the congregation to slow down their busy mind and focus on the words you are using to praise God.
"Let's assume you hear 2 sermons: One that is supplemented with 30 messages slides and one that has 3 message slides. Which one do you think you are most likely to remember? You guessed it: The one with 3 slides. Less IS more, especially if it is done creatively. I'd rather you give me 3 images than 3 bullet points."
The Few the PowerPoint Slides for Sermons the Better:
A good rule of thumb is the 10/20/30 PowerPoint Rule for a sermon/teaching. No more then ten slides, approximately twenty minutes, and no smaller than a thirty size font. This is helps you keep the teaching concise and focused. Also use images for the visual learner and words to help the text driven learners.
"My thought is to apply the "less is more" principle to how we present our weekly announcements, whether it's an actual staff member mentioning the top announcement(s) of the week, or a video that highlights the top 2 to 3 things that need attention. It's simple logic that people are more likely to remember 1 or 2 announcements than they are to remember 5 or 6. If retention is our goal, why do so many of our churches make numerous announcements?"
Keep Announcements To A Minimum:
Announcements can take up way to much of your gathering/meeting time. Keep them to the church wide announcements and/or for highlights/corrections only. If you have a bulletin make the most of it. Make the bulletin easy to read and easy to find information that the church is looking for. Keep the descriptions simple and to the point. That way you only have to make announcements for the major events.