Here is a nice bit defining what a Grot Whirlybird is, and what it does. This comes to us from a different source than what we read earlier this morning. So definitely something is being worked on along these lines.
Check this out, and please remember that rumors are rumors, salt is always required. These are early rumors.
via an anonymous source (different source than this morning)
Grot Whirlybird -
*Looks like a old Vietname War Hellicopter, big bulged bubble cockpit/body, skinny tail boom.
*About twice as big as the ork DefKoptas. Concept is the doors of the main body open on the
bottom like an old bomber to drop the Grots on to the battlefield.
*Cannot carry Orks or Bulky/Very Bulky models.
*Can drop Grots at any point along path travelled in movement phase only if not Zooming.
*Placement like deepstrike, but scatter is reduced if hovering.