I'd like to compile a great list of tips on keyword research. I will start it off with a few that I use...basic but sometimes those are the gems we all shouldn't forget.
Some ones I would recommend are.
1. Target long-tail keywords- in other words..."weight loss for middle aged men" is a better bet than "weight loss"...if you had a product on weight loss and you targeted that keyword...you might dominate it.
2. Check the PR of the top results in google- (Google PageRank Checker - Check Google page rank of any web pages)
See the results, type in the top 3 and see what the PR is...if you submit an article to a high PR (EZA and buzzle.com both are 6) site and it has a PR above the top results...there's a good chance you'll be the top listing.
Those are 2 things that I do when I do keyword research. I've had pretty good results with them.
What are your strategies?