from more affected machine, A3 updated to late 03/03, nvidia-current, @ login
process logs would be refective as before
Over time and use the diff. would likely grow slightly

$ free -m
             total       used       free     shared    buffers     cached
Mem:          1000        801        198          0         55        169
-/+ buffers/cache:        576        423
Swap:          380          0        380


reverting libcairo2 to 1.10.2-1ubuntu1, removing a few other packages in addition to version# dependent ones to allow successful unity login
$ free -m
             total       used       free     shared    buffers     cached
Mem:          1000        446        553          0         55        172
-/+ buffers/cache:        218        781
Swap:          380          0        380

Reverting libcairo2 doesn't represent even a tmp solution, too many potential issues, ect. So it's a future fix or nouveau 3d on this hardware