Nick
What are they actually offering? Is this akin to a full service pre-employment screen that would be done by someone who's say, goiong to work for a bank? Or is it literally just interviewing the references?
If it's just literally interviewing the named references I can't see why people would pay for this. Tjhjey're might be some value add - these interviews are only as good as the person who is doing the interview. Myabe there is some benefit to having an experienced third party doing it? But this is a very weak maybe.
Are they also checking educational qualifications and other certs etc. Things like bankruptcies, CCJs, bankrupcies, verifying the criminal records cert is bona fide etc? Probably this is useful, but it would depend on the cost. Given the proliferation of nannies from outside the UK anyone who could evaluate their credentials and take up references in a foreign language WOULD potentially be very useful. These sorts of things in the 'real world' tend to cost around £200-500 for a UK national I suspect it could well be significantly more for someone from abroad. So, not a small cost for a family - anyone inclined to pay this is likely to go through an agency to recruit anyway (for better or worse).
However, not just anyone can provide this reference checking' sort of service if it includes some of the other info I discussed for various reasons. There is regulation involved. That's why I would be interested in hearing what the provider is actually saying they can do.
There may be some families who might prefer the degree of anonymity in giving references one of these services could provide.I suspect many people MIGHT be inclined to say something to a third party that they wouldn't say if they thought their comments were attributable. But this isn't entirely straightforward either - in the US it is not even allowed as part of a 'pre-employment screen.' The person has the right to see all the feedback provided on them and we know in the UK you are not allowed to say anything in a reference, if it's a performance issue, which hadn't been discussed during the employment.
So, they're either providing a basic service anyone could do themselves or they're trying to do something more sophistocated which they're right - not just anyone could do, but I really wonder how well THEY'D be doing it given some of the issues involved.