After the famous (notorious?) Penguin Update by Google, it has become essential to be more meticulous about the anchor texts while building backlinks for your websites. Now, if you just focus on certain keywords and leave a link everywhere with the same, you're risking being penalized severely.
Pay some attention to the overaall context of the page you're building backlinks from. Try to strike some relation between the page's contents and the anchor of your backlink. Concentrate on your favorite keywords, but also consider using their synonyms or phrasal alternatives.
