If you find you are hitting a plateau with regard to the weight loss, and you are exercising regularly it's worth checking your body water percentages.
Fat can only hold around 25% water, where muscle can be up to 75% (think those numbers are right, someone please check them). So if your weight is holding steady but your BW% is climbing its reasonable to assume you are putting on muscle mass and losing fat at the same time (provided you are in calorie deficit).
I find that I go through 2-3 week stages at the moment, where one week in three I lose no weight at all then suddenly it starts dropping off again. During the plateau my BW% steadily climbs.
Bear in mind that the type of BW measuring devices available to us mere mortals can be reasonably un-accurate, but seeing a trend in increasing BW% is a pretty good sign that things are happening in the fat loss department, and to be honest just knowing that is enough for me to stay motivated even if it carries on for a few weeks at a time...
Hope that helps