As a firm fan of the seriews since the beginning first impressions are indeed awful. The intrusive HUD elements completely ruin any sense of immersion or suspense. The very first thing I did was work out how to turn everything OFF (at least the game is fully configurable) with the sole exception of some of the blue highlighted climbing points which I never did manage to disable.
After that its full on Thief again, and I've spent sell over 25 hours in the game so far. There is loads to find and do, and the sense of body awareness is great. Its worth making sure you find and complete all the sub quests in each chapter to fully appreciate this.
No regrets with this purchase, and I hope the bad reviews haven't damaged our chances of DLC or a sequel.
Firm thumbs up to the Dev's. Shame they left the HUD stuff on by default though.