minor corrections:
In that case, you wouldn't have been able to upgrade libstdc++6 while powertop was not recompiled against it with a binNMU (and 2.8 was uploaded at some point in september), or powertop would have to be removed.
2.8 was uploaded in November, not in September, but a binNMU (2.6.1-1+b1) was scheduled on the 17th of August for this libstdc++ transition. -- Manuel A. Fernandez Montecelo <manuel.montez...@gmail.com>