Your question was very helpful to me in getting LaTeX working with Anki, but I've found there's an easier way to get dvipng:
- Install MacTeX. I installed BasicTeX-2011.pkg (MacTeX-Additions-2011.mpkg is NOT required).
- Open the terminal, type "tlmgr update --self && tlmgr install dvipng" and press enter. It will update TeX Live Manager and install the latest dvipng.
Once you do that, you should be all set.
