i have been on top 10 from last few months for my website using a specific keyword . i m doing social bookmarks for this keyword from last month and suddenly Google dropped me to third page with this keyword ....... i m confused why did Google do so ??? need your help guys..........
Have you overdone the density of keywords in your site - in which case you MIGHT have a penality for spamming. Likewise if all your backlinks have the same anchor text Google might discard some??