I haven't see the 3rd Camel, but I remember vividly when I got my copy of the 2nd Camel how different it was from the 1st Camel.

All sorts of things had changed, not least of which the language (perl4 -> perl5). The Cookbook section was missing - ahhh!

That said having read both books from cover to cover I think Camel 2 was a great improvement on Camel 1 - if a similar amount of effort went into the change to the 3rd version then it will be excellent I'm sure!