Ever since the nofollow attribute was added to the roster of usable tags, it’s caused no end of problems. Should you nofollow this, nofollow that? It seems like the only clear advice is to nofollow that creepy guy into the woods.
We’ve written about nofollow before. When it’s used on links coming in to your site, that’s fine; PageRank isn’t as important as the presence of the link anyway. When it’s used on a link going outwards from your site, it’s up to you how you use it. A good idea, generally, is to nofollow any link to a destination site you wouldn’t want to recommend in conversation. If you don’t want to encourage anyone to visit it, don’t use a followed link and give the site additional benefit. And, of course, there’s no real reason to nofollow internal links at all.
In general, if you’re linking to a spam site, you might be better off not actually making it a hyperlink. Sure, you might refer some traffic over via seeming organic search, but you don’t show the backlink as coming from your site.
The specific question here is in regards to blog…