Katy Perry wore a fishtailed Marchesa gown to the 2009 MTV Europe Music Awards, just weeks after Blake Lively got leggy in a shorter, and feathered, version of the same style at the "Where the Wild Things Are" premiere in New York.

Because both dresses bear the same intricate flower embroidering along the shoulder (which is by far what makes each design), I'm going to have to give this one to both ladies.

What I think is particularly interesting, however, is that each star's pick seems more characteristic of the other's personal style.

Which style is the right way, and which one needs to hit the highway? You tell me in the comment section below.

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Photos (left to right): Ian Gavan/Getty Images; Jim Spellman/WireImage