I duly submitted our concerns via the links posted above (thanks for posting those, BTW). No reply (by email at least) from BA but I've just checked my BAEC account and found that 10,000 miles have been credited for service recovery. While I'm not one to complain about receiving ex-gratia miles I have to confess to feeling just a little bit miffed. A reply from BA explaining the cock-up or at the very least apologising for it, and an assurance that it won't happen on our return flight (which was the main thrust of my email to BA) would have made me feel much happier about the situation.
This has happened to me too, miles first without apparent explanation. But I then received a letter shortly after (even though I had raised my lost luggage complaint by email).
I suspect that whoever deals with complaints actions all the response at the same time, the miles credit immediately, but the letter takes a little longer to reach you. Sending a simultaneous email would solve the problem, but I suspect that a real letter is better in these situations.