Which is the better option in 2012, sub-domains or sub-directories?

[yahuie]

Pinnion offers online software for surveys and trivia games. Information about our product is at www.pinnion.com and then interested users create their accounts at secure.pinnion.com. The surveys that they create link back to secure.pinnion.com, so we would obviously like to gain whatever SEO benefits we can from that structure.

We've been advised that moving from secure.pinnion.com to www.pinnion.com/secure would be the best way to accomplish this. A 2009 post by Rand seems to support that POV, but then a 2011 post over SEObook claims that everything has changed 100% since then. There was a little conversation here and here in Q&A last Fall that touched on this subject, but nothing really definitive.

Would love to get thoughts on this subject based on the collective wisdom today. Thanks.

[Syed1]

It depends on the kind of content you are going to have there. As you mentioned, if you expect good quality inks and a lot juice there, I'd suggest doing it on a sub-directory.

However, if you are going to be creating many pages that could be considered 'thin' (little/no content pages, no backlinks at all, no images, etc), I'd say go with the sub-domain so as to have a buffer of its possible repercussions on the main website.