Richard Kirk wrote an interesting and in depth artcle on SearchEngineWatch.com. The article is a good primer for those looking to start out doing SEO on their own and want some steps to follow with regard to which keywords to optimize for.
One interesting point from the article is worth reading for domainers who rely on the Google Keyword Tool.
From the article:
But First, a Note on Search Volume
Search volume data from the Google keyword tool is bullshit. You know
it, I know it, the whole industry knows it. You look up the search
volume for a term, then log in to the tool and do the same thing again –
the search volume is completely different!
The simple truth is: you shouldn’t rely on individual datapoints coming out of Google's keyword tool. It’s really there for illustrative purposes only.
On the other hand, it’s the only real source of data on any keyword;
Analytics is only going to give you data on stuff you already rank for.
So you’re stuck with the Google keyword tool as your comprehensive and
easily-accessible data source.
You can use a simple equation to try and reduce our reliance on
individual data points that come from the Google keyword tool; we call
it “relative search volume”.
relative search volume = individual keyword search volume / total search volume for all keywords
By dividing the search volume for the individual term by the total
volume, you get down to focusing on the proportion of the total audience
rather than the raw number of searches. It allows us to place the
search volume in context, which is crucial for properly judging how
important it is to target a keyword.