McLaren is pushing on with aerodynamic development while Honda focuses on getting its power unit up to speed. The most notable update seen on the MP4-30 chassis at Malaysia is the addition of an S-duct in the nose cone, undoubtedly pushed by Petr Prodromou who worked on the feature with Red Bull in recent years.
Similar to the inlet on the Red Bull RB11, air is caught via a wide channel underneath the entire span of the nose cone, with the outer extremities however feeding channels to provide cockpit cooling rather than the S-duct. Different however is that on the McLaren, the duct splits in two, provided an exit on each side of the pitot tube hub fixed on the car's centreline atop the monocoque.
http://www.f1technical.net/development/467