I think Jeff's great, and I don't really care what the numbers girl is like. The new one doesn't have Vorderman's strong personality (yet), which may or may not be a good thing.
Anyway, I think just about any TV show would be improved by not having Des O'Connor in it -- hell, even Des O'Connor Tonight would have been better without Des O'Connor -- so I much prefer the new Countdown. It's years since I watched the show regulalry, but it's now back on my DVR's list of things to record, because it seems fresher and much more fun, like the good old days.
As for Richard Whiteley, I sense a certain rose-tinted nostalgia here. Was he really that good? I always thought he had a touch of Alan Partridge about him. I liked how he was intelligent and well-read but didn't show it, but I also found him just a little bit... creepy.
Jeff Stelling could maybe ditch the corny start-of-show routines, but otherwise he's an excellent host.