I measure and weigh myself for competition, and I have noticed after being Paleo for almost 2 years now that my weight in around 8lbs heavier, given the same measurements. This is most definitely muscle and doesn't bother me, I was just curious if you noticed these same effects as well.
I was by no means skinny fat or overweight before, so it's kinda crazy to me that my composition has changed so much for the better. My six pack says thanks for Paleo.
I ate paleo during my formative years and when I was I desperate to gain weight. I attribute much of my results to eating this way. Muscle is more dense than fat, so swapping fat for muscle will reduce your size. That is why one can look like a dancer with clothes on, and then a fitness model with them off (i.e. not being emaciated but toned and tight).