Over the weekend the site and services will be moving hosting provider (the first of two moves), there might well be small pockets of turbulence but downtime will be kept to a minimum. Watch this space ..
Update: Looks like our interim hosting solution is not coping as well as hoped. I am going to begin moving over to (our hopefully long term) new host immediately.
Sorry to anyone who has experienced problems with the service, I am doing my best to keep things working.