It will be very interesting to see which way Virgin goes: integrate the workforce or keep them as penny packets.
The Qantas group seems to have taken the approach of divide as much as possible. From what I can tell, from a pilot employment perspective, there are mainline, Jetstar, Jetstar NZ, Jetstar Asia, Jetstar Japan, Jetstar Pacific, Eastern, Sunstate, Network, and Cobham all operating flights on behalf of the Qantas Group (might have missed a couple of Jetstars, its hard to keep track). There is some ability to move between companies but it is limited and not consistant.
It is my understanding that this is a deliberate strategy to ensure that the workforce is not able to exercise as much power as it would if it were all combined.
Virgin started off with a number of companies: Virgin Blue, Pacific Blue, Polynesian Blue and V Australia but for some time has been working on bringing them back under one company due to the belief that the the overhead of running so many businesses exceeded the benefits. The Skywest set up was a shift away from this but it may be temporary as the ATR operations are already Virgin branded and the Skywest west coast ops will all move under the Virgin brand. Tiger will apparently stay as a separate brand for the forseeable future.
Whilst there are always winners and loosers in the short term when seniority lists get banged together I can't help but think that in the long term there will be more winners in a combined pilot workforce. And more importantly it doesn't have to be at the expense of the company so Virgin can remain profitable whilst doing so.