I had the same problem Rich, it seemed like I would get bulk messaging every morning, sometimes 40 emails. Not sure how it fixed itself, I changed all my settings on the forum to other random settings, then changed them back to how I wanted them. That seemed to sort it.
This problem is mvagusta.net specific for me, I get the individual thread emails OK ( mostly), it's the bulk daily emails I'm not getting eg all the new and updated for-sale forum messages in one email.
I've unsubscribed and resubscribed, no difference, they come some days and then not for a while and then another appears at random... It used to work fine, every day I would get an email for each forum I'm subscribed to ( Brut, Maintenance, for-sale etc) with all the new and updated messages from the previous day.