Get the Best Keywords for your AdSense and AdWords

What is the best keywords for our site or blog? I always use the AdWords Keyword Tool to analyze my blog for the best keywords. You can just enter the URL of your site and the tool will analyze all available keywords and will display the search volume for each keywords either for last month or average. It also display the advertiser competition and average CPC for each keywords. Other options also available. I think this tool is also very important when you want to select or setup and advertisement in AdSense. I use it to select the keywords that have the highest CPC and it really works. I've tried that in one of my blogs and the ads keywords that were chosen from this tool have better CPC rate.

Another tool I just found today is the Google Search-based Keyword Tool. This one is still in Beta and I don't really understand how Google make this instead of having the AdWord Keyword Tool. You can read more from the page or in a posting by Vinshe. If anybody knows the pros and cons of this tool or have better suggestion please share them here.