Here are slides from a longer course (Tampere, 2010).
Henric Nilsson has kindly donated code that substantially improved summary.gam and related functions and plot.gam.
Thanks to the following (incomplete list of) people for bug reports suggestions and help. Nicole Augustin; Mark Bravington; Louise Burt; Liz Clarke; Mark Clements; Peter Dalgaard; Anthony Davison;Sharon Hedley; Kurt Hornik;Pierre Joyet; Andy Liaw; Thomas Maiwald; Henric Nilsson; Jari Oksanen; Charles Paxton; Greg Ridgeway; Brian Ripley; Evi Samoli; John Szumiloski; Alain Le Tertre; Luke Tierney; Brian Williams; Jim Young.

Finally, I am particularly grateful to David Borchers and Chong Gu (anonymously!) for first suggesting making these methods available in S and Mike Lonergan for a good deal of helpful discussion and many useful suggestions about numerous aspects of the package (including the idea for and earlier code for vis.gam, and the earlier versions of the negative binomial code.)