It would be very useful to have a way to specify some important HW requirements for apps. For example, in machines that have only 1GB of memory, it is very important to tell the user which games may not run very well in their machines. Hence, memory is a very important entity to be added.

I thought CPU could also be important, but as previously pointed out by @ximion , it may be difficult to express the different values that each CPU has. So maybe for now we just add the memory spec.