Negative comments, or comments not in line with the editorial "slant" of the paper are more often than not deleted.
Try posting anything critical of global warming on the Guardian UK ---deleted
Post something critical of the central banking system on Telegraph UK ---delted
The comments are pointless they are there to create a false concensus and to trick people into the idea that they have some sort of "say" in the matter.
There are a lot of fairly "extreme" comments (pro gold, pro-Ron Paul, anti-Obama) that were not deleted. It seems odd for them to delete Bitcoin related comments considering the article mentioned it. My comment was just trying to clear up false information propagated by the author.