In your place, I would get a measurement of the fat percentage of my body. The best method for doing this is underwater weighing which is not easily accessible to most people. (I am a member of my local Fitness 19 gym and they bring a mobile lab around once every 3 or 4 months with the equipment.)
In the alternative, you can do a measure of fat percentage using calipers and a fat percentage chart. Most weight loss physicians provide this service (it's very difficult to do on yourself). I'm not sure, but I think you can have it done at a Jenny Craig center, as well.
Finally, there is a chart that plots your weight against your wrist measurement and waist measurement for a fairly accurate measurement of body fat percentage. It's not as accurate as the first two methods, but it's adequate for most practical purposes.
I think you already know that you are losing fat, but any one of these methods will show you exactly how much and that should really motivate you to lose more!