A version of Google that exludes backlinks as a ranking factor is much worse according to Matt Cutts the head of Google’s Webspam team. Someone asked Matt “Hi Matt, does the big G have a version of the search engine that totally excludes any backlink relevance? I’m wondering what search would look like and am curious to try it out.”
Matt Cutts often answers webmaster question related to the Google search on YouTube and sometimes on his blog. He answered the question about a Google version without backlinks as a ranking factor too:
He says that they don´t have a public version of the Google search that excludes backlinks as a ranking factor but they have an internal version and experimented with it but he says that even if there is a big noise, backlinks are still a really big win in terms of quality for search results and the internal version that excludes backlinks as a ranking factor did show results that are much worse compared to the current Google version that does look at backlink importance.
His answer is comprehensible. You can´t kill backlinks as a ranking signal due to the fact backlinks are still important. Many websites link out to other websites and Google is already very good in recognizing web spam. That means there is not even a reason to kill this ranking factor as web spammers kill their projects on their own so that most of the time only quality websites will rank very good.