What happens if any of these fail? HP is offering a fair amount of security. The object store, for instance, makes three copies of every object and pushes them into different zones, each with backup power and dual Internet connections. HP Cloud handles the work for you. Some other services, such as Google's Compute Engine, leave the replication across zones up to you -- then bill you for bandwidth in between.
There is a big difference in the tone of HP's marketing. Google's literature might have been written by engineers, lawyers, or -- an even more careful and paranoid group -- engineers who went on to law school. Google's documentation continues to play up the potential failures in data centers and talks about potential failures and downtime for maintenance. It's your job to plan ahead.
HP Cloud seems more optimistic. There aren't as many options for customizing how your data is protected, and that's probably a good thing for users who just want to store their data and trust HP to replicate it three times.
If you want reassurance, you can sign a service-level agreement with HP, which offers basic terms on the HP Cloud website. If some data can't be found for a few minutes, HP will start offering service credits up to 30% of the bill.
HP is adding some other services to round out the product line. For starters, it has well-structured libraries of Ruby, Java, Clojure, PHP, and .Net routines, and these are finding connections in other places. There's a Drupal plug-in for dumping your Drupal data directly into HP Cloud's object store. HP is also partnering with companies such as New Relic, the makers of a performance monitoring toolkit already integrated with HP Cloud.
HP Cloud is playing catch-up. The more established players such as Amazon and Google have much more elaborate lists of options. But HP Cloud offers much of what a growing firm might want: OpenStack machines at an introductory beta price that's quite good. HP is counting on open standards and easy portability being the carrots that attract people looking for well-priced machines without any lock-in. That's a good mix.