I havn't kept up with the tread, but my vote went to iPhone 4s. I played with both the Razr and the Rezound in store a few times over the past couple of weeks. The Razr was fast and I personally thought the screen was pretty nice despite some things I've read being anti-pentile. However, I just do NOT like the feel of the razr in my hand. I can't really say why, but I even asked to feel one that was not attached to Verizons display to get a better feel, I just absolutely did not like the razr feel at all, and could not see myself using that phone on a daily basis. That is, of course, a very personal decision though and really would just depend on the person and perhaps the size / shape of their hands.
Regarding the rezound, I actually really liked how it felt in my hand. From video reviews I saw, I had expected the phone to be MUCH thicker, but it was really a perfectly fine thickness for me. However, sense UI is just not my cup of tea. Now, I know I could probably root and install custom ROMs eventually, but at this point I'm kind of looking for a phone that I can just use, I'm getting busier and busier and really do not want to spend a ton of time customizing my phone or installing custom ROMs and kernels just to make it work suitably for me. Getting back on topic with the Rezound, as I said, I strongly disliked sense UI and despite packing decent internals, I felt the phone was relatively un-smooth compared to the Razr and iPhone. I will say though, the screen was also quite nice and definitely very sharp! Didn't listen to any music to comment on the beats, didnt want to stick the headphones they had on display in my ears

.
Anyways, now for why I may go with the iPhone 4s. First, it is available now (some places are backordered, of course). I'm getting kind of tired of seeing rumors of a release date over and over and constantly getting closer and closer to the end of the year. My second reason is smoothness. Playing with a friend's iPhone 4, everything seemed extremely smooth, transitioning from screen to screen, opening and closing apps, pinch-to-zooming (?), etc.
That isn't to say the GNex will not be smooth. Most videos I've seen prove it to be quite smooth and have great features, which is why I'm very anxious to see the phone. I also am on the fence regarding the screen size. The iPhone fits very nicely into my hand and I think it feels great, personally. Some of the larger android phones have felt not so great to me, so it really just depends on the shape and size so I NEED to see the phone in person.
Regardless, have an iPhone ordered, and my theory is, if the GNex releases within my return window and I like it, I'll return the iPhone and get it, otherwise, I'm almost 100% sure I'll be satisfied using the iPhone.