HSM in the Cloud is good for companies to secure the credentials of the services they deploy. This is more secure and more useful than storing them in plain text files on servers in the cloud infrastructure deployed at Amazon and other providers. So yes, it's a good thing.
That doesn't mean I'd trust it with my personal credentials. I don't keep any credentials in the cloud unless I'm forced to; but if a service that stores credentials for users is not using an HSM, then it's not a service you want to be using.
FWIW, OpenStack is doing a similar service called Barbican.