Blekko may not be a big player in the search space, but the upstart search engine is trying to make a name for itself by playing up its focus on eliminating web spam and content farms from its SERPs.

The company’s timing couldn’t have been better: Google is increasingly criticized over the quality of its search results, and many say the search market’s 800 pound gorilla isn’t doing enough to crack down on those who look to game it for profit.

Google seems to be getting the message. Late last month, Google’s Matt Cutts published a post on the Google Blog announcing that Google has been and will continue to implement changes that make it harder for spammy sites to achieve top rankings.

It remains to be seen how far Google is really willing to go, and how much of an impact its changes will have. But Blekko, with far less at risk, isn’t afraid to make bold moves: it has banned from its index a number of prominent web properties operated by companies with content farm models.

Banned properties include eHow.com, experts-exchange.com, AnswerBag.com and encyclopedia.com, all websites you’ve probably encountered in a Google search at some time or another.

Previously, Blekko had put together a feature that allowed its users to exclude these sites from search results, but CEO Rich Skrenta told Search Engine Land that twenty properties have been removed from the index entirely “based on our users [clicking on] /spam on results“.

Needless to say, Blekko’s move, no matter how bold, will go unnoticed by the vast majority of internet users. Blekko is nowhere near as big as Google, but its high-profile banning of properties like eHow.com and AnswerBag.com raises the question: should Google follow suit?

On one hand, fighting low-quality content with mass bans is, in some cases, akin to killing an ant with a sledgehammer. Yes, content farming has a bad reputation, but the truth is that there probably is a legitimate market for fast food content, in moderation.

On the other hand, there’s an argument to be made that, given the worst of what content farms are willing to publish, search engines shouldn’t necessarily have to invest significant resources in separating the wheat from the chaff on properties known to produce far more chaff than wheat.

In determining the best approach to take, Google might eventually have to consider the latter. Given the volume of information Google indexes, making even incremental improvements to search quality is probably going to be an increasingly complex and costly undertaking. That means that picking off low-hanging fruit, such as prominent content farms, may provide the most bang for the buck.

From this perspective, the question for Google may not be whether it can afford to ban websites with poor quality content profiles, but rather whether it can afford not to.