ok so i've spoken to a couple of people and the problem is present (also happens in 2011 sp1 x64), although it seems generally unnoticed.
i've been reassured that although some of the scriptjobs created are a pain, a couple aren't AS worrying as first thought as they're 'passive' -
"i.e. They only run when a certain callback is triggered, such as the Display Layers being updated." which are apparently different to the more dangerous "always running". obviously they're still there are they're still waiting for the trigger, im now curious as to how far back this happens.
try a simple test if you have versions other than 2011 x64 sp1 and 2012 x64 hotfix 4 -
start maya.
create nurbs circle.
- list scriptJobs - make a mental note on last scriptJob number
enable override
change override color
list scriptJobs - i get 4 new, i i cant remember but didnt stand out, 1 with a connection to the curves.notes, 1 event driven for attributeChange on the overrideEnabled and 1 noted as event driven for attributeChange on overrideColor but seemingly to update display layers.
if anyones able to post up their results would be much appriciated.