I know that I hardly have time for one of them, but greedily want to try all three. I wonder if there is an expectation for the course to be available again, or at least provide the full materials afterwards. And if there is a penalty for failing/dropping out of them due to time constraints.
You can find some of the materials for last year's ML class at http://www.stanford.edu/class/cs229/.
CS 221 had a similar one, although it got taken down recently. I imagine you'd at the very least be able to access the materials while the class is ongoing or shortly thereafter for archival purposes.
