Oops! Looks like I forgot to announce the release of ATF 0.9 here a couple of weeks ago. Just a short notice that the formal release has been available since June 3rd and that 0.9 has been in NetBSD since June 4th!
And, as a side note: I have added a test target to the NetBSD Makefiles, so now it's possible to just do make test within any subdirectory of src/tests/ and get what you expect.