HN is certainly a place to market certain political ideas (e.g. Ron Paul) - if you have a different opinion on these ideas, even if it is entirely sincere and polite, you are still modded into invisibility, as if it were trolling not to wish to vote for Ron Paul.

In this respect, HN is (or has become) just like Reddit.

There is a huge editorial bias, even if it is not the perennial 'Hacker News favors YC companies in some insidious way' and even if it isn't 100% from PG himself