I just received this hoodie and have worn it a few times. Overall, I'm pleased with my purchase. I bought this looking for something very lightweight that will keep the bugs off me at night during the summer. It certainly accomplishes that. I live in Minnesota and we get our fair share of mosquitoes at night. Thus far, I don't know if it's just by virtue of having long sleeves on that helps keep the bugs off, or the new 'Insect Blocker' technology that Columbia is now marketing. Either way, it serves it's purpose without overheating you. It is very lightweight; I'd feel comfortable hiking through the woods in this because I know I won't sweat too much in it like some other sweatshirts.
I think the fit is relatively true to size. If you know your size in anything else from Columbia, it will probably translate to this as well. I'm 6'2" and my weight ranges from 182 - 185 lbs; my chest is 41 - 42 inches. I bought a medium and I like how it fits. The zipper is a little stubborn to get started, but that's my only critique. Overall, I'd recommend it.