I'm currently in charge of updates to the M2 tutorial. I've just completed a major overhaul, geared at bringing the tutorial up-to-date with Opera 7.23. The next round of updates will focus on 7.5. Now's the time for comments on the tutorial. You can take a look at my current working version at http://people.opera.com/tim/m2/ or the current stable version at http://www.opera.com/support/tutorials/opera/m2/. Please add comments about the tutorial to this post. Thanks!
UPDATE: My changes have been added to the main tutorial, which has moved: http://www.opera.com/support/tutorials/mail/.

