For the rest of 2009, and probably through 2010, I'm planning to start looking at some more imperfections not covered in the book. Some of these will reflect reader feedback in the five years - is it that long!? - since Imperfect C++ was published; some will reflect my own further dissatisfactions with the language and its various implementations.
I don't have any firm plans yet to do a More Imperfect C++, but given the imminent expansion of the language with C++1x (formerly known as C++0x), it couldn't hurt to start thinking about it. Readers, and other interested parties, are invited to contact me with any ideas/imperfections they may have.