From a psychological point of view... (Score 3, Informative)

As an undergrad psychology student I recently had a few lectures delivered by a very up-to-date sleep researcher. First of all, circadian rhythms (our internal wake-sleep schedule, sort of) control (a) blood pressure, (b) heart rate, and (c) core body temperature. Despite unverified self-reports that conveniently occur in relatively deindividuated internet forums, I can't possibly think of how severely disturbing our circadian rhythms would result in normal functioning. Secondly, as some readers have speculated while actually reading the linked article, it would most likely take a lot of sleep deprivation to kill an otherwise healthy individual. Last, but not least, studies have shown that sleep deprivation for 11 days led to considerably increased slow wave and REM sleep for several nights thereafter, so obviously the mind is prepared to deal with sleep deprivation. I'd better get some sleep now.