I think that Desert Racing of BarDos is the latest commercial game developed for Amiga. It was released late 2005 IIRC.
There have been more recent commercial releases for MorphOS. Like Robin Hood: Legend of Sherwood at the end of the 2006 and Airline Tycoon DLX in 2007.
Then there's always new PD games and open source ports, but who can count all of them
I wouldn't count Myst as oldskool game.. at least in Amiga standards. I'd say it's one of the first newschool games for Amiga
