Here's a behind the scenes look at communication in a large church...
Our primary means of getting the word out on upcoming events is the weekly Worship Program. Our best way of getting people to register for events, ask for information, etc., is the Communication Card. For example, if we want people to sign up for Discovery, they can simply write "Discovery" on their Com Card and that means we can follow up with reminder calls and notes. This way of signing up has made a huge difference in many areas of ministry.
Here's the problem. If we collect Com Cards too early in the service, people don't usually have time to respond (especially since about 1/3 of us show up about 2-7 minutes after the start of the service). When we tried to leave Com Cards to the end (our experiment), it was simply too confusing. What works best is to take offering at the end of the service, but that's a downer of a way to end a service. We did this for months, but it just didn't flow well. It works if there's special music or some other special worship element, but since going to four services, it's hard to keep the worship teams here up to the end of the service every week.
So we're going to try another experiment. We're going to send out a weekly email that lists some of the upcoming events or items that require a response and ask people to respond to the email. This is a both/and approach because we will still use the Worship Program/Com Card method and we'll still keep trying to tweak the service order so that we can delay offering until later. But that's where we're at right now and we're open to suggestions.