Google alerts is a free services offered by the internet giant, which notifies you by email or as an RSS feed about a specific query or topic you provide. For example you can monitor who is talking or mentioning your name all over the web. Using this services Google will send you periodic emails (daily, weekly or by occurrence) pointing you to the sites that are talking about you, there are six types of searches (News, Web, Blogs, Comprehensive, Videos and Groups).
Twitter is a social website. This is a perfect place to listen to what people are saying about your company or product, you can even subscribe to an RSS feed of the search results. For example in 12/08/2009 my blog host (Weebly) was down and I couldn’t publish my new updates, trying to figure out what is happening I searched the Weebly keyword and got those results shown below, where everybody was complaining that the service was down.
Technorati is a blog search engine that lets you find out what people are saying about you within the blogosphere, The results can be available in RSS format, so you can subscribe to the various search results as well.
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