Personally, I think relating this to productivity is a flawed benchmark, though it is interesting to think about. The idea of tying it to the rate of increase for top executives (the 1%) is also specious. It would make more sense to tie increases to inflation, which we have not done[1].

Ultimately, minimum wage should be set so that an individual receiving it would be above the poverty line, otherwise, what the hell is the point? So for 2012 we should be around $11/hr. If you want to argue that you should pay your people so little that they'd be in poverty, then you should find a different country.

[1]: http://www.raisetheminimumwage.com/facts/entry/amount-with-i...