The last time around, the committee invented lots of features on the fly, many of which turned out to have far-reaching negative effects. (Think of the books that have been written on subjects like writing exception-safe code.) So I wouldn't lean too hard on "I know the committee thinks of backwards compatibility".
As an aside, I think that C++ has gone too much out of its way to not introduce new keywords. That's why, for example, the syntax for lambdas looks odd and reuses previous tokens, and the new nullptr keyword is not just "null." If you're unwilling to break old programs, then you can never clean up; think OSX vs. Windows, or even Python's willingness to break compatibility with version 3.