Hi, Glad you're finding it helpful! The reason I didn't include linear algebra is that it is possible to do the day-to-day work of most entry level data science jobs without it. That said, it is great to know for a deeper understanding and if you are writing your own machine learning algorithms. This MIT OCW class provides a good introduction, with video lectures and problem sets: http://ocw.mit.edu/courses/mathematics/18-06-linear-algebra-...
There is more discussion on this topic here: http://www.quora.com/Big-Data/What-concepts-of-linear-algebr...