There is a basic opinion on the net that „PaaS Is The Future Of Cloud Services“. I also share this opinion but I go one step further: „Development-as-a-Service is the future of Platform-as-a-Service“!
Platform-as-a-Service (PaaS) helps you to host, debug and execute your application over its whole lifecycle. Therefore PaaS offers an infrastructure stack (like LAMP, WAMP, etc.) which generally implements the OS, a webserver like Apache, a database e.g. MySQL and the programming language e.g. PHP, Ruby, Python etc. Good examples for PaaS offerings are Google AppEngine or cloudControl.
For using PaaS solutions you have to develop your application on your local machine and upload it to the PaaS infrastructure afterwards. There you can execute it etc. That means you still need a local IDE (integrated development environment) like Eclipse and you are not able to work on the code parallel from different machines. Ergo: The PaaS offering is „just“ useful for hosting and executing your application.
What developers really need is a Development-as-a-Service solution on which they can hack their code without using a local IDE. And because of the demand of working and developing things distributed still raises the need for hack on the code parallel from different locations growth.
Really cool is that you actually have a fully intergrated (best of) stack of IaaS + PaaS + SaaS. So you are able to deliver your application one-stop from one platform: code + debug + deliver + done (next loop)!
Image source: http://mb-c.pro