No, absolutely not. I would be dead without it, as would many other college students.
There's a common misconception that Redbull has as much caffine as 5 or 10 cups of coffee, but that's absolutely false. IIRC, it has about as much caffine as a shot of espresso, or about as much as 2 normal cups of coffee.
Actually, a single 8.3 oz can contains 80mg of caffiene, which is comparable to a light cup of coffee (caffiene content of coffee: 80-130mg for a 6 oz cup)
Its other active ingredient, taurine, aids concentration.
Also believed to limit muscle fatigue, prevent excessive weight gain, and regulate the nervous system. According to wikipedia.