I used Apple Garageband 2 for this countdown - I now have Garageband '11, which gives you a lot more options on instruments and settings, although i have no plans to do another BBC Countdown, at least not until 2012.
As per comments - I wanted my audio to end on zero because there are so many people who have criticised the fact that the current World News countdown does not do that. So i wanted to go back to the idea, that was introduced in the 2005 BBC World countdown, of having a few seconds of extra music.
So if it feels tacked on, its because it is.
Musically, nothing is "tacked on", the 3 chord motif features heavily through the last 30s, in place of the original World Motif. The thing I feel makes it sound disjointed is the 1999 ending sound that I put in the last 6 seconds.
When that's removed, the countdown flows straight into the ident.
I'll try and post a sample of the countdown without the 99 motif so you can have a listen.
Thanks again for all the comments