Not to belabor the point too much. I've tried to pull detail out of a few images. Where I've gone into Aperture, and created 2 new images from an existing one, +/- 2EV. I've been able to go creative, get artsy, but never actually improve the overall image.
Here are a few images I've capture using +-2 EV (usually exposure time), that there is no way I could have otherwise captured what my eye saw.
I've taken a few pictures of bridges, where HDR has allowed me to pull out the detail of the beams. With just a single exposure, the rivets on right side of the image where barely noticeable, as they where in the shade. Pulling in the detail from the +2EV image really, IMNSHO, gives the image a lot more interesting detail.
The following image could have really used +-4EV as well, but without HDR there is no way I could get the bike and the center tree/clouds visible in the image.
I've still got A LOT to learn. To all of the other posters, and to Dave for starting the thread, THANKS, for inspiring me.