Nice article published in rediff.
I am going to quote heavily from the article, mostly for people who are lazy enough to click the link and read the article.
The study argues that difficult decisions are best handled by our unconscious minds.
The study -- published in the journal, Science -- showed that conscious thinkers could make the best choices about simple products, while unconscious thinkers could make the best choice among complex products.
Apparently, thinking about things consciously means a person can only focus on a few things at once. When it is a tough decision to make, therefore, the mind can sometimes give certain factors undue importance. Thinking about something for too long can also lead to different evaluations and inconsistencies. Unconscious thinking, on the other hand, can handle large amounts of information that can lead to a fairly evaluative summary judgment.