I'm not going to rehash the good points about Cloud Computing, how great it is, and how everyone should be using it, because that's old news now! Instead, I'm going to talk about a problem with Cloud Computing, and this largest of hold backs could soon be resolved, starting with the Open Cloud Manifesto.

In order to build a true Cloud app, one of the key features is it should be able to scale up (and scale down) on its own as required. One of the main draws of Cloud Computing is not having to pre-invest in infrastructure and hosting in the hope your app will grow. You build your app to monitor its own environment and load levels, and then communicate with the infrastructure to start and stop instances as required.

The big thing holding back companies from using many of the true cloud platforms such as AWS and Joyent is that at the moment once you build an app for that platform, it is then tied to that platform in a big way. The reason for this is that the methods of controlling your instances and services on the platform are all API based, and none of these APIs are shared between providers.

This means that unless you explicitly build functionality for every known platform into your design, your application will be held back by all of the below:

Your app will not be portable. If Amazon went bust tomorrow, you would have to rewrite your app for another cloud provider.
You cannot guarantee security. You can't trust an unknown quantity to hold your information.
Dependency on another company's standards - if Amazon chose to change the way their select statement works, they can do so with no warning and your app will be down until you fix it.
An open standard for communicating with cloud providers would give freedom to move your app around from host to host, and even possibly pave the way to a "cloud abstraction layer" where you run your app across many cloud providers providing supplier redundancy and globalisation.

The Open Cloud Manifesto is a motion backed by a lot of big names to standardize the APIs and methods used to build cloud platforms. The aim is to bring together the large cloud providers to not compete against each other on certain key points such as database usage, or reinventing existing standards.

You can read more about the Open Cloud Manifesto on their website.