Your poll is confusing. If you meant that what type of bookmarking is useful for SEO I'd go for social bookmarking in sites like facebook, digg, stumbleupon. Needless to say, ALL THESE sites have rel="nofollow", so in theory, they'd be useless to rank better.
This article can give you idea on how social bookmarking help in SEO: http://www.ngbconsult.co.uk/seoguide/2010/05/social-bookmarking-seo/
Try and google for a list of bookmarking sites. Incase your blog/site is in a particular niche, you may want to consider googling for bookmarking sites in that niche. Better bookmarking sites frown on posts/articles which promote affiliate products, so be careful. Read the ToS before you start bookmarking.