There are a great many programs on the market for analyzing your logs and most of them are quite expensive. It's really a godsend for a small office entrepreneur. This software is called FastStats and has just about every powerful feature you could imagine. Quite frankly, I don't think it's worth your time or your money. Now, that's just my opinion.
Some people swear by that type of software.
I just don't think it's worth it. I formerly used this type of software myself, but found that it just didn't do the trick for me. My server logs told me everything that really made a difference. Tracking other stuff ended up just being a big waste of time for me. Now, as for actually getting the formula that gives high ranks, the Keyword Density Analyzer is still your best bet.