I choose to highlight only the top 3 search engines here because the only meaningful search traffic comes from these online properties. As "Web 2.0" or "social networking" becomes more of the system of how the average user finds what they are looking for I will highlight those properties here. Examples of these are Digg.com or MySpace.com
Currently Google is the most popular tool for searching the web. MSN and Yahoo are not even close. Google SERPs results in the past year have been the topic of much discussion on SEO forums. Unfortunately mostly bad. Since Google is the most popular search engine, it is also the most spammed. To combat this Google internal algorithmic features have consistently given honest webmasters and websites fits. One of the most popular ones being the infamous Supplemental Index.
All in all, the results are still very fair, but are STIIIILLLL based WAY to much on IBLs.
Some Google tools:
Yahoo
Yahoo now owns search properties Inktomi, Overture, AltaVista, AlltheWeb.com, and Kelkoo.co.uk. Yahoo's search index is powered by Inktomi old-school spider SLURP. Yahoo is generally the slowest at updating its results. When they do update they send out "Weather Reports" on the Yahoo! Search Blog. In general I feel the Yahoo results are a good mix of research and commercial based results. KBK has worked on optimizing the Yahoo directory website in the past. We have become very proficient in earning coverage on Yahoo! Search over the last few years. One thing to be careful on is cross linking co-owned websites with them.
Some Yahoo! tools:
MSN Search
Microsoft is known for constantly reworking its software products until they get them right (we know it as wrong), and MSN Search is a shining example of the company putting that same effort into an online product. The company now crawling the web with its own crawler, MSNbot. The are constantly working and re-working the results and have been the fastest search engine to index and reindex changes on websites. Fresh results are MSN's specialty, meaning you make change on your website and you can expect it to reflected in the MSN SERPs within days.
Some MSN tools:
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