“SEO” - another long shot
Single word search phrases like 'SEO' are rarely worth spending too much time focussing on for several reasons. They can generate huge volumes of traffic but often the relevance between the term and your website is tenuous.
Chasing a single-word phrase usually involves using all your ammo on just one phrase and weaking your site's performance for other search terms that might produce much better returns. I'm sure that being no.1 on Google for 'SEO' would bring me some business but it's almost certainly going to be more realistic to aim at 'professional seo' or 'seo Cambridge'. (mjbdata.co.uk is currently no.1 for 'seo Cambridge' and 'Cambridge seo').
By focussing some efforts at gaining a ranking for the top relevant search term that chances are you might improve your position for related multiple-word terms.
21/12/2007 : I'm not actually going to look, yet.