Hi Matti,
Thanks for your reply - very much appreciated.
I realised that from digging through the details, like you say - our atom.xml feed was broken, so I've updated this in wordpress and feedburner to our
http://blog.xpango.com/feed/ and tidied up a few of the subscription links and then ping'd feedburner once I'd made the updates.
Amazingly just a few hours later an email notification from our Blog with a year's worth of posts! So it's great to see this working and it looks as if it has back dated too.
To answer your question, we have about 8800 email subscribers to our feed and then 5,022 actual subscribers (I presume via RSS) - so hopefully our subscribers will now start to receive some emails too.
I will follow through the rest of your suggestions to make sure everything is in order, especially the MS Word text.
For anyone else reading this thread, it seems to me as if Feedburner will send your emails as normal, you just need to make sure everything is in order so definitely worth checking for problems.
Thanks again,
Jon