Very interesting topic you are raising here. However, I think it should come with a disclamer: “Works for really awesome workplace!” (Like Google, Facebook and other hot tech companies). It is very many hops to go over and as a potential employee, I should feel confident it is worth it. Too many places aren’t.
I do agree with commenters, that not everyone has an online portfolio. Partly because we we work on proprietary software and also due to the fact of having life besides coding.
Audition project - again, would work for very in-demand workplace, if you are not that sexy company, competent people will most likely not bother.
Cultural Fit - absolutely! Unfortunately, it is difficult to tease out during interview, as applicants are going to put their best foot forward. Perhaps only trial period can really show it.
Doing pitch - which position are you trying to fill?
It does not make much sense to me for a more junior one, with little administrative/managerial responsibility. Developers, who can pitch and do great presentations would command a hefty premium, because it is often way out of typical developer skillset.
It is better to hire a developer and teach him pitching/selling if it is that important, though I have yet to see it being necessary outside startup environment.
On the tangential note, I really liked Joel Spolsky’s take on hiring. You just need a person, who is a good cultural fit, smart and get things done. http://www.joelonsoftware.com/articles/GuerrillaInterviewing3.html