I wish the documentation was more clear about (C++)...
Given the power available under the hood, it's sometimes easy to forget that the Arduino is targeted at an audience that may not have or want computer science expertise. For those more interested in tinkering then learning a sophisticated object oriented programming language, C++ appears as more a deterrent than an attraction.
I think the Arduino documentation has it pitched just right, focus on what you can do and how to do it, and don't let the technology get in the way. For those of us that are as interested programming languages as we are in what we can make with them, discovering there's C++ under the skin is easy to find. I do agree with Mikal that it is a pleasant and welcome surprise.
But lets be careful that we don't create an impression that any knowledge of C++ is important for making a successful arduino project.