On Monday I've met with Matthieu Hug from RunMyProcess in Paris, an interesting start-up company in the "cloud". Their focus is pretty easy: Integrate the cloud - with what you have internally and with other cloud services. At CeBIT 2008 I've done a presentation about "SaaS" and related topics (we didn't use the term "cloud" at that point of time). One of the three major issues I've discussed as threats in that area (and would mention nowadays as cloud threats) is integration. How do you integrate external cloud services with other external services or internal applications? Some of these services provide a set of web service interfaces. But even then, integration is a tough work.
RunMyProcess now provides an external "cloud" service to do that integration. They provide pre-configured web services of a series of (external) cloud service providers, including Salesforce.com, SAP BusinessByDesign, and GoogleApps. And they allow to define processes which include one or more of these products. That allows to build integration between such services and existing internal applications. It as well allows to enhance cloud based services like GoogleApps. Matthieu told me that some of his customers are adding workflows to GoogleApps to replace Lotus Notes (even while I'd recommend the customer to consider LotusLive as an option in that case...). And there are some companies starting to create added-value services by integrating and enhancing cloud services, creating sort of "industry clouds" or "community clouds".
I like the approach of providing an integration platform in that way. It doesn't solve every problem (and more complex platforms built on top of classical application servers might provide some more functionality) but it is an answer to one of the biggest threats in the cloud. Thus it is definitely worth to have a look at that solution. And it is just another example of the amount of creativity unveiled by the cloud evolution.
If you want to learn more about the cloud, you definitely should attend Cloud 09, Dec 2nd-4th, Munich. And you should always have a look at the Kuppinger Cole webinars. We do webinars on cloud topics frequently - and there are many recordings of cloud webinars available.