Comparing search engines is sometimes like the parable of the blind men and the elephant. Do you test popular searches, or do you test obscure ones? How carefully do you examine the results pages? How do you compare special results, such as when Google suggests relevant news articles?
But compare we will, and one Web site makes it a little easier. You enter your test search once, and the Bing-vs-Google tool searches both engines, then offers the SERP from each side-by-side (or, if you prefer, above-and-below).
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Click for full size screen shot
In this screen shot, I did a search related to a problem I've got with the touchpad on my HP DV3500 laptop. I accidentally misspelled "touchpad" and Google, as always, offers the correct spelling; Bing says they've got nothing on "tourchpad" and I should try to spell things the right way.
It's a helpful shortcut for folks who want to do lots of test searches. See http://bing-vs-google.com/ .