I stumbled upon this freely downloadable EBook (though you can also buy it at Amazon in Print) called Essential Skills for Agile Development (external). You can download it as PDF from www.AgileSkills.Org (external)I haven't read it yet, but it seems like a nice recap of some of the most essential skills a developer would want to learn first. they specifically state they are going for the 80-20 rule: teaching the 20% of skills that gets you 80% there in terms of agility.