No I don't think that it will effect the current up and coming story line, but it certainly did put closure on the Doctor/Sarah relationship for me. I always felt that was one very big gap after Tom's Doc dropped her off on Earth before Deadly assacin.
But what a superb ep, I mean K9, come on what a brilliant little dog he really is
Was really quite sad when they blew him up in that exploision, I really did think though that wasn't the last we'd see of that robotic little dog. So wasn't a surprise when the TARDIS de-materialised and there was K9 standing proud.
I don't think that was the last we'll see of K9 and Sarah though, possibly in the next sries, well I reckon we'll see them again, for possibly more than one episode, ok that would be nice, but who knows what the BBC have up their sleaves.
Cybermen in 2 weeks guys, really looking forward to that one