Speaking as an unreconstructed C and C++ programmer (C-octothorpe? Wha' that?) I like the idea of writing C/C++ for Flash. K&R perfected programming syntax and semantics 30+ years ago - one language to rule them all and one language to bind them I say!
But... unless Adobe manages to wedge POSIX, libc and MS's C library, the STL and (please oh please) Boost into Flash most of those millions and millions of lines of existing C/C++ code are not going to be terribly useful to Flash programmers.
If, on the other hand, Adobe is going to expose the WIN32 C API and co., or libc, inside Flash then all Adobe will have achieved is to make Flash as dangerous as ActiveX (or whatever MS is calling ActiveX these days!)
Editor: you need a hand icon with the thumb horizontal.