I did this as a volunteer through a local ambulance corps. It's very interesting and rewarding to know that you are helping someone in need. Keeping records of where your crew is going is also very important and interesting as well.
Everything Lori said. I worked at a small college so it wasn't as hectic as, say, a 911 job. It was a great job, but you have to be the right kind of person for it. You can burn out fast because it's very stressful and you have to deal with some difficult stuff. You never know what's gonna happen from day to day...sometimes it'll be dead, sometimes you'll be doing five things at once. If you can handle this and the emotional drain and get focused instead of stressed when you get an adrenaline rush, this is a good job to have. Pay is lousy though.
This is a demanding job that is often misunderstood due to the inaccuracy depicted by pop culture and media. It takes a unique person to not only handle the technical operations but also have the customer service skills to calmly handle citizens in crisis using only your voice. A person must be able to compartmentalize emotions to prevent taking the stress home. It is a rewarding job in that you are helping many people every day, but also thankless because the dispatcher is the forgotten part of the first responder system.