As for air intakes they seem to be mostly for noise-fluff at the moment. K&N's version seems to add the most air-sucking fx to the SHO soundtrack, I personally went with the Airaid though, as they offered a dry-filter design (no oiling). It only added a little bit of turbo noise.
There are some more advanced air intake designs in development, as I understand it, but I haven't seen any products come forth from those efforts just yet.