My two cents on this is that it should be possible (or the default) to have it logging the IP address.
Having said that ted, yes, DNS is not "reliable" in some sense - on the other hand the reverse lookup *is* information that can be useful, and in the case of dynamic DNS it may contain information that you do not get after the fact. Saying that "if we put it in the log people will rely on it when it's potentially unreliable" is crap. Anyone past the age of puburty on the internet knows full well that reverse dns is not necessarily reliable - OTOH sometimes it *is* useful information - to be treated with a grain of salt. We should not *prevent* it from being collected because it is not useful in all situations.
