With the exception of the Cayman/Boxster twins, traditional German sports cars tend to be overlooked. I don't think about the BMW Z4 that often even though I generally like it, in particular the sDrive28i fitted with the TwinPower Turbo 2.0-liter engine. None of the changes to the 2014 BMW Z4 will likely change this because few of the changes are that noticeable.
From what I can tell (and I'll leave it to you to suss out the big differences) it looks like they've added a Bimmerang similar to the one seen on the BMW 3 GT only turned horizontal. They're settling on "gills" as a name for these. Nope. It's the Bimmerang. Get used to it.