I copied the statement below form the AAMC website
I’m still in the early phase of my pre-med courses, but i, like many others, plan to take the MCAT 2014 before all the 2015 changes.First, I don’t know what the writing Sample section was all about since i’ve never taken the MCAT, or prep- MCAT,i’m just happy they are taking out something having to do with writing since i personally hate writing. I’m a science and math person.
So for those who already took the MCAT this year, did you do the voluntary, unscored trial section. If so how was it, what subjects were included in the trial, were you compensated and how?
https://www.aamc.org/students/applying/mca t/faq/31…
“If you plan to take the MCAT exam in 2013 or 2014, please note that the Writing Sample section will no longer be part of the exam. In its place, a voluntary, unscored trial section will be added to the MCAT exam starting in January 2013. The unscored questions on the Trial Section will test content that will be added to the MCAT in 2015, including content in psychology, sociology, and biochemistry. The Trial Section will consist of 32 questions and will be administered in a 45-minute time period after all three operational sections (Physical Sciences, Verbal Reasoning, and Biological Sciences) have been administered. Including the Trial Section, the 2013 and 2014 total testing time will be shorter than it was in 2012.
Examinees who volunteer to participate in the Trial Section and put forth a good faith effort will be compensated. The Trial Section will be administered under standard conditions for all examinees who volunteer to participate and scores will not be reported for this section.
Please note that admissions officers will continue to receive Writing Sample section scores from exams taken in 2012 and prior.”
I’m not sure why i can’t edit my post after 24 hours. Anyway i meant to say for those who will take the MCAT this year, after taking the MCAT please share your feedback on that new section.
Well I haven’t taken the new one yet, but from what I’ve read online, they ask you at the end if you want to do an unscored trial section. For a good-faith effort, they email you an Amazon gift card code for 30 dollars (but the exam price went up 30 dollars so AAMC is cheap 
) But anyway, about a week before scores come out, they email you how you did (e.g. 45 percentile) along with your gift card code. The section is either pschology/sociology or biochemistry. It doesn’t affect your score either way if you do it or not, it’s completely voluntary. Some people found it hard, others found it easy, depending on their background I guess. Most people put in random answers it seems, lol.
For those who do take that trial section, can you please post general information here as to the level of difficulty of the new questions? I’m interested in knowing the extent of knowledge required on the psychology/sociology questions and whether an introductory class covers the content. I also want to know what level the stats questions involve (or if you encounter any) and the same for biochemistry.
The AAMC is gathering information on these questions in gearing up for the MCAT in 2015; they’ll use the info they get from the trial section to calibrate the future test. Having preliminary information on the level of difficulty of the questions will help premeds on this forum gear up for the new exam and prepare for it.