I'm not a huge IR fan...a bit too fantasy for me most of the time. The contrast is very cool, and the sky is awesome. Yeah, there is a bit of a grain to the sky I wish was smoother, but thats probably more persoanl preference than anything.
Recently I've started playing with a layer of gaussian blur in my skies when they do this to achieve a more smoother look. I doubt you're interested but if you are, I would be glad to share the technique, just hollar. Great photo!
I think this works great in infrared. I love all the subtle shades of grey. I think the composition is absoultely fantastic. The blurry/whispy clouds are great, though I can't tell if that was done with a long exposure or during post processing (or just how they actually looked). Great overall tonal range.
I love the black and wite/ gray feel to this one. The hight also gives it a litle something extra. Over all a fabulus shot, but one thing bothers me, i feel the sky is a tad to dark at places, over burnd maybe? Don't know what it is but over all nice job!
P.S. Show us more of your work so we can see more of your stile :)