I'd like to use ExtJS4 for my next project. However, I'm new to Ext and not that well versed in Javascript's finer points either.
There are a couple good books about ExtJS3 available. Should I learn from those old books first and then apply the knowledge to v4 or has the API changed so much that there is no point in learning the old one first?
If not, what's the best way to learn for an Ext newbie?