Massimo, thanks again for the insights. It's great to hear from you and I look forward to the new direction the Arduino team is taking making ever-more powerful processors accessible to the general public. It would be great if you or other folk on the leadership team could consider commenting from time to time elsewhere on this site regarding decisions such as the non-adoption of Pauls suggestions re: malloc.c to fix the Strings library once and for all.
I didn't mean to sound like an advertisement re: Pauls teensy, BTW - I have no financial stake in PJRC, etc. just a customer of a single board while I have bought several official Arduinos. I simply admire the board for what it is, a full-blown 32-bit ARM processor on a tiny footprint that is easy to breadboard.
The Due features an incredible processor that offers way more options than the current board footprint seems to have space for - unless you start mounting components on both sides, I suppose. External RAM, Ethernet, etc. to name a few.