I've started something now
Here what i do Cakey.
I generate an HDR in photomatix. I then tone map as follows. set the strength to 100% set the light smoothing to Very High. And Micro Contrast to maximum. All other setting at default. I then adjust the luminosity, white point and black point to give a full histogram as possible, but pay attention not to blow any highlights or burn out the shadows.
If you want an even darker feel then run it through photomatix again and tone map the image again which will produces an even flatter image, but play around with the white and black point and luminosity to try and get a spread on the histogram.
The MAIN TRICK is PHOTOSHOP. Photomatix just gets you started. I dodge and burn, extreme S curve, brightness and then flatten. I then change the mode to LAB and alter the colours via levels with the A & B tabs. I may desaturate some colours as well (any method will work with the desaturation) I then reduce the noise and work it with a mask to keep the main points sharp. I some times add another sky and more often than not I add a texture.
All of the above images are old works about 4 yrs old and not what I can produce now. Its just a case of practicing and experimenting. Remember that the key to It Is PHOTOSHOP.
To avoid blur in the foliage due to the multiple exposures.
I get round this by taking the multiple exposures and then i take a single correct exposure.
I generate the multiple and then i create multiple exposures from the single one. once i have the two sets generated i open both in photoshop and then mask the still leaves over the moving once.
Hope it makes sense.
Hope this helps. If you get stuck give us a shout.