I can see that. Moto may have assumed the DX2 would be "easy", since mature hardware and OS to work with. Ditto on Gingerbread, since mature harware that was already released.
None the less, Moto might be in a "Catch 22".
1. Release the devices ASAP (July) to get back on track with their 2011 business plan for revenue and perhaps have issues that would further hurt consumer perception.
2. Take their time to make sure the firmware is fairly stable, but risk August/September release dates.
Four more weeks may seem trivial, but not if they want to avoid a much more public DX2 or Gingerbread update debacle- but with the DX3 and Bionic. This assumes a scenario that the firmware for those devices is not stable already. Could be stable for both already- so no harm, no foul.