Driving nanny to distraction

Have you ever found yourself in traffic behind one of those lorries with a 'How's my driving?' sign on the back? The same idea is being applied to nannies in New York City with a website, HowsMyNanny.com, 'run by a prosecutor who is also a mother of two'. Parents subscribing to the service can have a 'licence plate' attached to their child's pushchair bearing a unique identifying number and the website address, and any 'concerned citizen' can report on their nanny's behaviour when they're out and about, via an e-mail relayed to the parent. HowsMyNanny makes some reasonable points defending its practice, including the usual one that 'professionals will have nothing to hide', and it encourages praise as well as tattling. But questions do remain - what about nannies who cover up the (locked on) licence plate? What about malicious false reports against the nanny? What about the rest of the time when nanny and child are not out in public, or about the children who are too old for a pushchair? Most of all, what about trust - what sort of relationship can such an employer and their nanny have? What do you think? Drop us a line - but don't rat on anybody, yet!