2011 WRX here.
I know that the iron section between the turbine and compressor sections on our turbos will develop surface rust pretty much immediately, but the other day I noticed a discolored section. Not sure if it's just from water dripping in through the scoop (it's rained on and off over the past few weeks) or if it could be a leak (is that an oil or coolant line?)
There's no oily residue or anything -- when I touch it it just feels like rust. It's not wet now AFAICT.