Of course one must keep in mind the fact that wikipedia is also notoriously full of [censored].
It is a C-class article, though, so the information should be about right. And I only looked up and copied stuff from Wiki because I couldn't be bothered typing it all out myself. Most of the stuff on that list has references you can check if you doubt the article itself. For example, from a http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Sleep_deprivation?OpenDocument made by a government body/organisation:
Symptoms of sleep deprivation in advlts
Symptoms of sleep deprivation in advlts include:
Constant yawning
The tendency to doze off when not active for a while; for example, when watching television
Grogginess when waking in the morning
Sleepy grogginess experienced all day long (sleep inertia)
Poor concentration and mood changes (more irritable).
Lack of sleep impairs performance
Let’s say that a person who needs eight hours of sleep per night only gets six. This two-hour sleep loss can have a major impact including:
Reduced alertness
Shortened attention span
Slower than normal reaction time
Poorer judgement
Reduced awareness of the environment and situation
Reduced decision-making skills
Poorer memory
Reduced concentration
Increased likelihood of mentally ‘stalling’ or fixating on one thought
Increased likelihood of moodiness and bad temper
Reduced work efficiency
Loss of motivation
Errors of omission – making a mistake by forgetting to do something
Errors of commission – making a mistake by doing something, but choosing the wrong option
Microsleep – brief periods of involuntary sleeping that range from a few seconds to a few minutes in duration.