Is this good use of HDR?

I do not have a whole lot of experience with in camera HDR so i was curious to see the results when i used it down at a local park.

i decided to give it a try due to the wide light ranges; the well lit sky, the dark trees, and the pond sort of in the middle

how do you think they turned out?

also, is there any way to use HDR in camera on RAW? Nikon grays out that option in raw mode, they make you switch to jpg

http://nature.desktopnexus.com/wallpaper/1800089/

http://nature.desktopnexus.com/wallpaper/1800087/

note: i took pics in non hdr mode, and the trees were much darker that in these.

Looks like a reasonable use of HDR, especially if shadow tree areas were much darker (exposure was for less interesting sky) without HDR. There isn't a lot of interesting stuff in the shadow areas, so a better use might be getting in closer to the lighted trees over hanging dark areas on the right of both photos and having HDR pull out "good stuff" whatever that might be.
Trees reflected on water came out good but water is a bit dull - no water plants or tree stumps or animals (turtles, etc.)

Actually the HDR technique was developed to provide excellent images even when the dynamic range of the scene was broader than that of the cameras sensor.

It was mostly used when shooting indoor architecture when the deep shadows under furniture as well as the view outside needed to be recorded. Without HDR, the windows would be blown out and the shadows would be totally black, no detail.

Landscapes can benefit from this if you do not have a graduated and filter to hold back the exposure of the sky.

In just what seems like a few months after HDR was introduced to the general public, artists started using the technique to create surrealistic images by over processing HDR images.

I have a link to one I created using the HDR tool in Photoshop CS5 As you can see, it is grossly over processed

EDIT: I have also posted an indoor architecture shot NOT using HDR. Had I used it, the view out the windows of the beautiful trees wold have been in the shot.