I also voted for a large and stylized UI and that may be due to nostalgia, but nostalgia is also a part of the reason why I backed P:E to begin with. More specifically nostalgia for the mood, atmosphere and a sense of being transported into a completely different world that I felt when I played the Baldur's Gate series (my all-time favorite games ). A large factor in this was the UI and more specifically the smaller details: the stone-like appearance of the console, the way the buttons looked like they were carved by hand and the intricate clock in the bottom corner. Not to mention the beautiful portraits. For me, the UI sets the tone for the game and therefore feels important to me.
I understand why the floating style UIs appeal to people. Aren't they popular in MMO style games (I haven't played any, so I apologize for my ignorance)? The fact that the player can customize how they interact with the game can be a big plus. Also, I am sure there are many benefits for this kind of UI in fully 3D games where you have to move the camera around a lot. I personally just don't like the aesthetic.
However, I wouldn't be horribly disappointed if the UI ends up not being as blocky and space-consuming as the ones in the BG series, as long as the general feel is preserved. If the dialogue box in update #62 or the UI mock up are any indication, I have nothing to fear. I especially like the wood grain and, well, everything about the dialogue box. Whoever you are UI artist, you did a great job! Maybe if there is enough time, and this is most likely wishful thinking, we could have the option of having either a more old school UI or a more customizable and floaty one.
Edit - I also wanted to mention that the scripted interactions look very nice and present an elegant alternative to cut scenes. Secondly, I hope that we don't see a radial menu like the one in Torment. It's probably just me, but I just couldn't get used to how it worked in Planescape: Torment.