If it's published by WotC (as successor in interest to TSR, Inc.) and has the DUNGEONS & DRAGONS label on it, then it's D&D, and if it isn't/doesn't then it's not. Doesn't mean I like it or am interested in it (personally I think TSR took a wrong turn with D&D somewhere around late 1975 and has been to greater or lesser degrees on the wrong track ever since), but I don't buy the argument that certain editions "aren't D&D" or are "D&D in name only," or especially that certain other games (such as C&C or Hackmaster) are "more D&D than D&D."