Nolan Hester has written a very nice review of NetNewsWire. He also mentions some glitches—the most serious of which I think will be fixed in the upcoming beta (1.0.1b3).
The most-common-by-far crash in recent versions of NetNewsWire occurs deep in Apple code, in the HTML rendering code. So I’ve managed to completely remove one call to this code, and I may have figured out the problem with the other call. (A multi-threading issue, of course.)