Meh. While I'm not personally bothered by the twist, I doubt this will last. To me, this is the new series equivalent of "the Doctor is half-human." Yes, Doctor Who's "canon" is very fast and loose (the old series has three different versions of Atlantis), but there are some fundamentals that you don't mess with unless you want to anger half the fanbase.
Anyway, I've been slowly going through every Classic Who for the first time, and that's been surprisingly enjoyable. Then again, I'm on the Tom Baker era, when the show was at its height. Once I get to Colin Baker, though... I might just skip to McCoy's second season.