Some very quick observations, based on having compared changes in voting results at specific companies.
Average oppose vote is definitely up by a fair bit, but the average abstention % is slightly down. It's a small shift but may confirm a) what I've heard from people that some managers have reduced/stopped abstaining and b) what I've seen when looking at voting records of UK institutions comparing 2010 and 2011.
Most of the big defeats do not seem to reflect long running concerns, in the sense that in the previous year the level of opposition was low. The exception is WPP, where there was a big vote against last year. Still the increase in opposition to tip it to a defeat this year was pretty big, but not in the same league as the others.
Flipping it around, two of the defeated companies last year saw big drops in opposition this year. One of last year's losers saw the biggest drop in opposition in the group of cos I looked at.