The Tools

Bootstrapping an exsting debian arch is dead easy, as you point out. Cross-bootstrapping a new one or a variation, or a new-compiler rebuild is still very difficult, but linaro is doing good work on that front. Emdebian did useful work on this front, but that work showed that without suffient buy-in upstream it was a massive job to maintain. The linaro/ubuntu tie-up has provided that upstream buy-in, so people actually care about cross-buildability as well as native building, and painless developer tools to use that functionality. This stuff, combined with multiarch to remove a whole boatload of cross-path-pain and general bodgery should mean that cross-bootstraping actually becomes something that works, as does cross-building when necessary/useful.

In the meantime of course powerful new arm boxes and convenient form-factors make native-building dead easy too, just like it is on your x86 desktop.

Expect to see some interesting stuff in this area over the next year. It should all be rather spiffy :-)