Some basic rules that I follow that never seem to let me or my fishing partners down.

1. When in doubt, don't post.
2. When in still in doubt, ask. If successful, ask others in your party on the day you fish if they would mind if you shared any info (and what info specifically).
3. Known go-to honey holes on known rivers are generally acceptable, but see rule #2. If its still "no", find cooler fishing partners.
4. Revealing true "zipper lips", hot techniques, lures or baits is NEVER acceptable and its your responsibility to understand the difference and be respectable to your fishing friends and the hard work and hours they've put into finding said success.

Just my $0.02 worth....