Looks like there's a new sequel to the original Ultima Underworld games, fresh finished:
Underworld Ascendant
No clue how (if) good that one is, yet. It's available through Steam only it seems, and I'm averse using that due to it's DRM policy. Doesn't look bad if not exactly up to today's standards, though there's barely any screenshots on the website.
There also seems to be System Shock 3 in the making:
System Shock 3
There's some news on that one's progress on the forums, looks like it will take a while yet.
Both games also seem to be made by the same team, notable Warren Spector and Paul Neurath who were behind the original old games.