The x3 is a great phone, everything you need and nothing xtra and unnecesary to slow the processing... It just needs a minimizing function! im sure a software update with the function incorperated in it would work...
Yah that would be intersting if Nokia provides it. But there are some other tricks with which we can do that S40 V5 & V6 phones, but it might be risky.
And Nokia can think of Providing some menu where we can see the List of applications that are running in the background. As of the version 8.40, the phone pops up a message if the resources are full and still if we try to open another application.