check out the Ray Wenderlick tutorials, really well explained, up to date with storyboards and really well paced tutorials.
Our staff loved them, and helped them get up to speed very quickly.
http://www.raywenderlich.com/
The tutorials look great, thank you. I'll give'em a run through. I like setting time frames whenever I'm trying to learn something new. Just as a reference point, how long on average did it take for your staff to get up to speed?