I'm another one voting #2. Colors seem a little more compressed with loss of shadow/increase in dark area details not visible on #1, and the details around the sun itself and breaking waves are the giveaways for me (unless, of course, I'm wrong). They're both very fine and appealing photos. I find myself drawn to the sun and sky in the first and the foreground more in the second.
HDR is one of those things that starts out as a very cool toy, and evolves in one of a couple directions (at least for me) - 1. Using it to make the normal look perpetually abstract, 2. Using it to make the "unlightable" look well lit, 3. Using it occasionally, if at all, because you just can't seem to figure out what else to do with a situation but you like what you see in the frame and you're willing to try anything, or 4. Using it as a crutch because you're tired of tweaking all the little stuff in LR or PS all the time. I'm falling into the 2 category, with some 3 as well. I really liked being able to make some wild looking stuff early on, but it seems more like "art class" and less like photography to me now the more I do it. That said, I'm still incredibly satisfied when I can put together a couple bracketed frames of a difficultly lit landscape and out pops this thing that I'm not sure I could have gotten with a single, well exposed frame.