How about the more general case of gray and black hat link building techniques? Especially in internet marketing and certain SEO communities, everything from forum profile backlinking to blog comments and mass article submissions are done daily to rank sites in all niches, not just the really spammy viagra-type sites.

There's a growing concern/consensus that in loads of non-spammy niches, the only way to get decent rankings is to build links.

I know this is naturally something that would be very hard for Google to tackle (since if 'junk' backlinks = domain penalty, black hatters would simply spam their competitors' sites with backlinks and get their competitors deindexed), but are there active efforts being made so that gray and black hat link building campaigns aren't (in some cases) pretty essential to a site getting good rankings?