Supernovae May Not Be Standard Candles; Is Dark Energy All Wrong?

StartsWithABang writes: The accelerated expansion of the Universe — and hence, dark energy — was discovered by taking the well-understood phenomenon of type Ia supernovae and measuring them out to great distances. The results indicated that they were fainter than expected, and hence more distant, and hence the Universe's expansion must be accelerating. But new results have just come out, showing that supernovae may not be standard after all. Does this mean dark energy may not be real, or that it may just be slightly weaker than we previously thought?