Amazon Web Services with PHP - planing learning curve

As many PHP programmers, I am a kind of CMS guy, but also training my "framework" muscles too. From what I observe, there is more demand for Amazon Web Services in job descriptions. Hence, they are worth learning.

But any learning should be well-targeted, with purpose, so I am asking questions below.

My question is which kind of applications (by architecture开发者_运维问答 and by domain) are the best targets for these services? Can you imagine some typical usage of Amazon web services that will most frequently be (is) requested by employers.

Does using Amazon Web services mean that not only I can fully migrate to this platform, but that partial solution is OK too - e.g. writing regular PHP apps on regular hosting that invoke Amazon Web Services (storage, cloud, queues)?

I suppose that the core target of Amazon Web Services and cloud frameworks in general are enterprise applications, but regular web applications that want to be scalable and flexible can benefit from these architectures too.

Amazon Web Services aren't a development platform by them selves. You still need to employ a technology like PHP or Java to build an application. The main difference from regular server based applications are the persistence layer and the deployment strategy.

Relational databases don't fit well in cloud applications. However, if you want to take it one step at a time, you can still launch an Amazon EC2 image (virtual machine), install Apache and PHP on it and mount an EBS volume with MySQL on it. This way you will have a development server like the ones you are familiar with. These are the first things you need to learn (start an EC2 image, create your own images, mount EBS volumes). I would say that the learning curve for them is not that steep.

However, if you really want to get benefit from cloud systems, you need to adapt yourself in a different philosophy. You need to consider alternatives to relational databases, like SimpleDB. You also need to learn clustering techniques. Most importantly you must design your application so that it is easy to add or remove machines from it.