Actually, the Abi is now prepared by the Ministry of Education of each of Germany's 16 states, the teachers themselves do not know the tasks until the morning of the particular exam. Since 2006 this is done in Lower Saxony (Saxony did this since 1992 btw).
Now you also have five exam subjects instead of four, with three Advanced Courses, a Basic Course in which you have a written exam and a Basic one with an oral exam.
The points you can get (they range from 0 to 15, which would be like F to A+, each point is one-third of the particular grade, so: 10 is B-, 11 is B and 12 is B+). This year is the first which has the exam result multiplied by four (until 2008 the results were tripled), and then the five results are added up. You require 100 points to pass, so it is obvious that you need at least 5 points in the five subjects (corresponding to a D), as 5*4=20 and 5*20=100. Nevertheless it is sad, somebody here in town failed too last year because he had 99 points

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By the way, it can be difficult if somebody would have to repeat this year: In Mathematics, they used to test Vector mathematics since 2006 to this year. 2010 will be the first year, in which Linear Algebra is to be tested (Matrices and so on). So there is quite a lot to learn for somebody who has to repeat.