It's a long, long job to research your keywords, keyword phrases, LSi's etc and then to write content for your chosen search term that has the perfect keywords, and the perfect density of those keywords. This plugin looks at the top 10 Google SERPS for your search term, compares them to each other, and then tells you the keywords that ALL the top 10 pages are using in their content, PLUS the density of those keywords. In less than a minute you will know EXACTLY which keywords and their relevant density to include in your website copy so that it matches Google's exact keyword expectations. Click here for more details.
Cross Platform – Being a Mac user I prefer when I can fire up a program locally. WordAi is web based and therefore works on Windows & Macs without issue (Linux as well). SpinnerChief III Ultimate has a Web Api that allows spinning from the web, but we did not have much luck with it, so at this time we consider SpinnerChief a Windows only application and therefore requires me to run it in a virtual Windows Machine using VMWare Fusion. This one is a hard one to call because clearly WordAi wins cross platform, but it doesn’t have all the extras that SpinnerChief offers.
There are some 'free' article spinners out there that require you to enter your text with properly formatted 'spintax' in order to create the end result. But how you need a totally separate tool to create this machine formatted text, so how is this really useful to you? Spinbot does all thinking for you, from taking in the context of every phrase to creating additional textual content that is as readable and meaningful as the text you originally entered.