Google's index is increasingly polluted. Let me give you an example, the other day I needed the exact address of an electronics store, I entered the name of the company and the street it was on. The top search results were "places to eat near..." - WTF? Who searches for places to eat near a named shop!? Similarly, if you search for "X review" you will mostly get pages that are just affiliate links to retailers and the text "Be the first to write a review of X!"
Right now Bing is a better search engine even if the only reason is that fewer people are trying to game it. The thing that makes Google most useful is searching other people's sites (e.g. adding +site:news.bbc.co.uk to your search terms). As a standalone service, they're going the way Altavista went.