I used to have a six-pack too.
My girlfriend was out of town for three weeks and my fat belly disappeared and I lost about 4kg. What it was, is she likes making desserts and baking sugary things for me. So it's the dirty old (low GI) carb thing that gets me too.
I too could do with the bit of muscle to make the ab's, well, look like ab's. Pilates of good for stomach and posture, plus it takes the strain off your back having a good stomach. A bit gay though.
With the temperatures going on over there I thought you would be on the Greek salads?