Drinking energy drinks are bad?!

Depends on your consumption.

A study done in 2008 documented no positive or negative health effects of the taurine found in red bull, however cardiovascular studies have stated that
"in a sample of 30 healthy young adults, had an immediate detrimental effect on both endothelial function, and normal blood coagulation. This temporarily raised the cardiovascular risk in these individuals to a level comparable to that of an individual with established coronary artery disease"

so what does this mean? well if you consume say ONE red bull, or a cup of coffee with creamer perhaps, no it wont have any immediate impact on your health.
HOWEVER, repeated usages of mass quantities of these products could cause long term adverse side affects. RED BULL is perhaps worse than coffee because its
1. easy and quick to drink, leading to excess consumption
2. advertised as a "party" or "fun" way to energize yoursefl. but if it was lunch time, would you get a latte?

so.... MODERATION

30 of reading on the interwebs