Nothing beats word of mouth for getting people to put their hand in their pockets. So it didn't take long for cheeky marketing departments to cotton on to the power of blogs and pose as consumers praising their own particular widget to the skies to help lift their top line.
Sneaky, perhaps, but usually legal. Not for much longer, however, as covert commercial blogging - or flogging - will soon be banned by Brussels.
Under laws due to come into force at the beginning of next year, but likely to be delayed until April for the UK, companies posing as consumers on fake blogs, providing fake testimonies on consumer rating websites such as TripAdvisor, or writing fake book reviews on Amazon risk criminal or civil liability.
The new rules are the result of the EU's Unfair Commercial Practices Directive, which is designed to do exactly what it says on the tin. Not only will it impose a general ban on unfair practices, but it will also include two main categories of unfair commercial practice: misleading practices and aggressive practices. Whether a commercial practice is unfair will be assessed in light of the effect it has, or is likely to have, on the average consumer's decision to buy.
The directive catches all commercial organisations - big or small - and the upshot is that companies (including sole traders) will no longer be able to pay individual bloggers or professional agencies to post false or misleading blogs or reviews online. Nor will they be able to do it themselves.
The directive is not just aimed at online activity, and a number of commercial practices will be unfair in all circumstances. This black list of practices includes "falsely claiming or creating the impression that the trader is not acting for purposes relating to his trade, business, craft or profession, or falsely representing oneself as a consumer". In other words, companies will not be able to pretend to be someone else, without clearly stating who they actually are.
But back to the web, and with sneaky marketing campaigns likely to be more effective than upfront marketing campaigns, what is stopping companies from simply risking it and continuing existing practices?
Those that break the new rules risk both civil proceedings and criminal prosecution. When it comes to catching the guilty in flagrante, the authorities will be allowed to make test purchases and enter premises without a warrant, if necessary.
But the crucial word here is "risk" - the government has already indicated that only serious infringements will be prosecuted, although it is probably best to assume that it will prod into action the Office of Fair Trading and Trading Standards, the chief enforcement agencies, should an illegal commercial blog gain a high media profile.
So it's six months (in the UK at least) until the plug is pulled on the blog flog as we know it. Of course, the new rules will not outlaw using these media, but firms will no longer be able to disguise themselves as a consumer without risking prosecution - and once it becomes clear that the blog or review is self promotion, some of its impact is likely be lost.
Whatever happens, the new laws are likely to have advertising and marketing agencies scratching their heads as they think up new (legal) online marketing campaigns. ®
Phillip Carnell is an IP/IT lawyer in the technology team at CMS Cameron McKenna