I agree that nothing on the list will ultimately land you a job at a really competitive company, but based on the wealth of messages I've looked at over the past months (yikes almost a year!), I think that many of those factors can be important in landing an interview. I have heard from friends (recent grads from top schools) that for many jobs, once get an interview you can land the job by nailing the interview; but it will be easier to get an interview if you have some of the things on the list.
I would say that a brand name MBA is probably the most important thing on that list - and it's what we've all been fighting for for many months now. For IB/MC positions, I have heard that 750+ GMAT might be the next most important thing, with a few friends telling me that that will almost guarantee an interview (combined with a brand name MBA of course). Name brand work experience is probably a big help as well - especially if the company is known to be very difficult to get into. I think merit scholarships are a good way to show you are a top candidate from your school - especially if your schools doesn't disclose grades.
On the other hand, I think that mba club participation is not a huge deal (at least on the resume) because it seems like everyone has it; I've also seen MBA clubs where every officer other than the president is a VP - social or finance or whatever - and is obviously just a way to pump up the resume. I don't really know how much undergrad school & GPA matter; I guess it depends on how long people have been out of school and what they have accomplished in the interim.
Regarding the Wharton girl's blog, I have heard that recruiting demands are particularly pronounced there. In fact, I read a recent article where Wharton was limiting recruiters to 3 visits per year - it was just getting too crazy for students with all the banks visiting every other week (a dozen times a year). I have heard that the situation may be different at other schools. I've met people from Michigan, Darden & Duke who have secured top IB & MC jobs after schmoozing with a firm just once or twice on campus.