It's not so much that it's soft, but mainly that it lacks detail. It has this watercolor-blotchy feel to it that is usually the result of over-aggressive noise reduction.
Just from my personal experience, I have had much more success by blending exposures instead of trying the tone mapping route. It always just looks fake and overdone. I'm pretty bad at doing the masking thing too but if you just play with it for a little while you start to get the hang of it. Or better yet, find someone who is good at it to teach you how to do it properly... seriously the masking is surprisingly easy, it's just that if you don't know what tool or approach to use it seems impossible but once you see someone do it who knows what they're doing, it's pretty straightforward and simple. Especially with the enhanced masking tools in CS5.
This time I put in a bit more color and brightness, and I tried to keep the cloud detail as well. Version 3 I was a afraid to do too much with the color and brightness for fear of losing the natural look. Now I'm willing to boost those some to get a pretty picture that is perhaps less realistic, but it looks nicer as a picture.