OK, here's my review. I've used this thing several times, and I absolutely love it. Totally worth the wait for me (missed the 01/10/08 woot). I was pleasantly surprised to find that the cardio machines at my gym pick up the transmitters signal. To me, that is AWESOME since I can keep my hands on the moving handles on the elliptical (precor) that I use, or I can check my heart rate without having to slow down on the treadmill.
This thing needs moisture to transmit a good signal. You can lick it, but after using it one time, I wouldn't recommend licking it again. That's just sick. Some people mentioned using vasoline, but I personally use lotion since it's water based. You don't need a whole lot either.
This thing gets excellent readings when I'm working out. HOWEVER, when I'm working on my chest, sometimes the signal gets thrown off for a second. That's expected of it though. For example, I'll do pushups on a barball that's on the floor, and sometimes the bar makes contact with the transmitter. Not a problem though; it picks it back up right away.
As far as comfort is concerned... I wore it for 24 hours the day I received it, just to get a feel for it, how it works, etc. I slept with it on too, and it kept reading throughout the night. Ideal placement (for me) is one inch under my nipples.
All you fatties looking to drop some pounds should look into this. It's an superb way to see how efficiently you're exercising.