AH!  You did it Keith - I thought clicking 'update' at the bottom would do it, but there's a little link hidden in some text at the top saying "rebuild the sitemap manually".

Finally it's done, thanks so much for your help!

Mark

Thankfully Webmaster World were able to provide some decent information, for those of you who have arrived here looking for a similar answer.

There is something called the "hash-bang" which makes javascript pages crawlable.  Hashbang refers to hash (#) bang (!) - so an example would be example.com/#!/page-1.

Here's a great place to read more, understand and learn to implement:

http://support.google.com/webmasters/bin/answer.py?hl=en&answer=174992

Cheers all!