Recently read an article about 8 seo tactics and their effectiveness, before and after the panda update:
(scale 1-10, where 10 is most effective)
article distribution: was 6, now 2
link on authority sites (gov, news etc): was 10, now 10
content sharing: was 8, now 9
directory submissions: was 3, now 1
guest blogging: was 8, now 9
link farms: was 2, now 1
press release distribution: was 7, now 2
social bookmarking: was 7, is 7