Well one thing to say is that you will not see a huge increase in the weight loss. I seem to remember SW saying that you could except an extra 1 to 1.5lb loss per month.
If you suddenly increase your activity level some people see an initial gain in weight but this is down to water retention and should soon pass. So make sure you are drinking more water - an extra glass for every half hour of activity.
However, they are lots of benefits to exercising in addition to weight loss - it will help with toning and if you do weight training as well as cardiovascular exercise you will build a bit of muscle which will make your body more defined. And muscle burns more calories than fat, not only when exercising but over the whole day even during normal daily activities - like surfing Minimins! Exercise has also been proven to improve mood and in some areas is available on prescription to people with depression. So you will also feel more positive, which can only be a good thing.
So go for it, but try to do a variety of different types of exercise rather than just the jogging.