Thanks Shaun, I've just had a go and it's the same.
The original problem seemed to be in editing replies, I now can't do that (guess they've timed out?) but in the original entry they're just showing as text, not emoticons
EDIT: Just gone back in and added a reply, that's working fine
Also, the original blog entry is, in fact, working fine, it just defaults to not allowing emoticons. As soon as that's ticked, it all works perfectly, thank you
Incidentally, I've set it to draft to avoid cluttering until I add some useful entries, just in case you wondered.