Im in the top two places in google for 'Top 10 Halo Guns' with me and my digg page, also Im first on the second page for 'Halo Guns' Also im second and third for 'Top Halo Guns'. I didn't even try to get those keywords, I was just keeping to my writing schedule.
I don't think submitting to that many social bookmarking sites helps because all I did was submit to digg.