Google vs Amazon Cloud
Dion Hinchcliffe from ZDNET tells us that Google App Engine is entry into a space that has been largely dominated so far by Amazon and its Elastic Compute Cloud — as well as a few smaller players like Bungee and Heroku — has turned the Internet cloud computing space into a fully-fledged industry virtually overnight.

Hinchcliffe continue: "..instead of just offering applications over the Web in the form of Software-as-a-Service (SaaS), Amazon and Google are actually offering an entire Platform-as-a-Service because they provide the foundational upon which to build highly scalable and robust Web-based applications in the same way that the traditional operating systems like Windows and Linux have done in the past for software developers. But what’s very different about this model is that no longer is the platform itself “sold” to the customer who then takes responsibility for running and maintaining it. In this model, it’s the very operational capability of the platform hosting that is the primary value here (and it’s how such platforms are typically billed). This has far reaching implications to both the business models of PaaS vendors as well as their customers."
Hinchcliffe continue: "..instead of just offering applications over the Web in the form of Software-as-a-Service (SaaS), Amazon and Google are actually offering an entire Platform-as-a-Service because they provide the foundational upon which to build highly scalable and robust Web-based applications in the same way that the traditional operating systems like Windows and Linux have done in the past for software developers. But what’s very different about this model is that no longer is the platform itself “sold” to the customer who then takes responsibility for running and maintaining it. In this model, it’s the very operational capability of the platform hosting that is the primary value here (and it’s how such platforms are typically billed). This has far reaching implications to both the business models of PaaS vendors as well as their customers."