well quite 
quick recap for the very pregnant:
Wimereux (my tip for the top). One really good restaurant, lots of OK ones. Long sandy beach with hard sand easy to walk on. OK shops - a few mum-friendly ones to poddle round (one particularly nice one with lots of little versions of those colourful cows that someone put all over London a few years back). Groovy Pas de Calais activities like a cowboy day where everyone dressed in slightly rubbish cowboy costumes and somebody found a horse to put in the little square bit. Only slight downside is it can get a bit crowded. But that is only PdC crowded. Even in the height of August it is empty enough to be a pleasure.
Le Touquet - you remember surely?
Hardelot - another good hard sand beach. Very long, quite empty. A little bleak for my taste - quite good dunes though. One parade of shops, nothing very mum friendly though.
St Cecile - same as Hardelot but a bit jollier.
Don't think I could stay for a whole week in either tbh (although both are only about twenty/thirty minutes from us and we've got a big garden with a climbing frame).
Merlimont - we've only just found this. It is a bit north of Berck. Seems nice. Bit bigger than Hardelot or St Cecile. Nice beach with toddler and buggy friendly sand. Haven't really explored it enough to know whether it would be nice to stay in for long.
There will be a short test on this next week.