Google recently announced their new product Google Apps Engine. This is a developer tool by which you can run your web applications on Google's infrastructure. That's mean you can port your application on google clouds, so massive infrastructure will be easily available, so no need to worry about scalability. It is free to start but you have to pay after certian usage limit.But the problem at this moment is you can write your application only in python. I am surprise why GWT applications are not supported there. It will be great if Google provides easy integration of J2EE Applications.
You can watch announcement of Google Apps Engine in Google I/O Seminar.
