At long last I finally was able to download Prey this afternoon. Playing on PC.
My initial thought is that performance is fantastic, so good that I can forgive it not being as graphically adept as other modern titles. When I started it up the first time I put all the graphical settings on "high" and I've easily been hitting 90fps (where I locked it with RTSS), just a few drops to the mid-80's. No need to tinker any further. I'm using a 480 4gb and a 6600k at stock for reference. I put it on my SSD, and was a little surprised the loading times were as long as they were - but that's a trivial compliant.
Prey controls really well on PC. I can't relate to the issues console-goers have had so far, but I've had zero problem tracking mimics. Quite a few have led me on merry chases all around the main lobby and staircases. I'm on the hard setting and died a few times already (a good thing). Sound issues from the demo are thankfully fixed.
Voice acting seems great so far, and I'm already pulled into the overall plot. The emails and logs around the station are all well-written and give the impression of a fully-manned space station. I like that all the people are named.... a nice touch that oddly enough reminds me of Morrowind. Some rooms seem a little empty, but most of the design is on-point.
Initial level design impressions are very strong. There's a couple roadblocks already that I'll need to come back to when I get some more neuromods, and I've used the gloo gun to get around a few encounters. It's an Arkane game through and through. I know people were doubting this because it's mostly a different team from Dishonored, but Colantonio was co-director of D1 with Harvey Smith, and it's clear he brought a lot of those same principles to the Prey team. It's a great mesh of gameplay mechanics and level design.
Two hours in, it's everything I wanted it to be. I might hold off on playing to see if they announce the hardcore/survival mode at the BE3 conference tomorrow. If available right away, I'd probably switch over to that.