I live in the SE USA, where it's generally 80-100% humidity in summer and still often >50% in winter.

Any full rain pants I've tried result in so much perspiration retained that I still end up wet, and also stinky too. Jackets are a little better situation since they are designed with vents and can mitigate perspiration.

I bought some Rainlegs a few years ago. They're designed to keep your crotch and thighs dry in moderate, scattered showers (not hard rain), and they work well for this purpose. Naturally, you need fenders on any proper commuter bike, and these help make Rainlegs work. They are normally worn rolled-up around waist like a fat belt, then deployed as needed by unrolling and pulling 2 velcro-ed straps around backs of your thighs. They actually work well and most of the time are as simple as snapping on a belt. Hard to find good pics of this feature:

http://www.velo.se/view.php?id=2411

http://www.rainlegs.co.uk/

http://www.wiggle.co.uk/us/rainlegs-leg-protectors/

I bought my Rainlegs at wiggle.co.uk, who gives speedy, free shipping to USA for order totals >~80 bucks. Wiggle has periodic 48 hr sales where i found the best delivered price anywhere on tubus racks and brooks saddles. It's a little silly that the best deal I could find was across the Atlantic ocean, and shipped for free faster than an order from Performance Bike in Chapel Hill, NC. Go figure.