Technically, yes, you can get more questions wrong and still achieve a certain % correct. But, you also now need to get more Qs correct to achieve that same % correct as well. Before the MCAT shortened and went on computer in 2007, the sections were about the same length they are now (there were only 3 multiple choice sections + an hour for essays + lunch and breaks) so it was still ~ 7 hour day, but less testing.
As for will it be easier to achieve a specific percentile score, I doubt it. The science it expects of you and how it tests you on that science really hasn't gotten any "easier" and even if you want to argue that it has (if you think Psych/Soc makes it easier, or that more biochem/less physics makes it easier), that means on average, other test takers will likely find it easier as well. The MCAT is still graded on a curve, so while for the next couple years the %-iles and what % correct corresponds to a given percentile may fluctuate slightly, according to the AAMC even if the early testers see a slightly different scale, eventually we will get a similar raw-to-scaled score/ percentile performance as on the older exam. So in the end, I would imagine that no, it will not be easier to get a 129 than it was to achieve a 12, assuming a 12 and 129 represent the same %-ile (right now a 129 is the 93rd percentile across all sections, while a 12 varied, being ~95th percentile in both PS and BS, 98th percentile in VR).
Long story short, to score in the top X% or better you are still going to need to beat 100-X% of all other test takers, and that's not getting any easier. Good luck!