Frederic1 - 7:59 am on May 4, 2006 (gmt 0) This is my personnal opinion.
Some people say "Yahoo and MSN provide more relevant search results than Google". Personnaly I won't switch to those search engines. Too many times my queries showed no results on Yahoo/MSN while Google gave me what I was looking for. Google Image is also in my opinion far more powerful than Yahoo Image or MSN Image. Frankly I don't think Google would stay #1 if their search results were so irrelevant :-) Spam is everywhere, and taking the example of MSN I have noticed than it's very easy ranking #1 if the search phrase is in the domain name (then you just need a few backlinks to rank#1). Also MSN has problems indexing pages which have many hyphens in the url. Yahoo has relevant results but it can be very slow to index new pages, moreover the number of indexed pages on Yahoo is weak compared to Google's, I often get no results when I use it.
This is my personnal opinion.