You have brought up some genuine concerns. Upfront, there's still a lot of work to be done, and we really need good testers and packagers. You have your own opinion of 64-bit ... and we are pleased to note that "it appears to be usable at the hobbyist level
" but the fact of the matter is, it is still in testing and there are still lots of wrinkles that need ironing out. There are apps to be rebuild and tested against the latest KDE (at the moment it's 4.8.3) and Qt. The latest kernel is being assessed.
In testing, we do not offer support and it is unethical to ask for help fixing broken apps and systems but we do look for workarounds and fixes. And there are broken apps, and breaking your install does happen. It's the risks, and a terrible one at that ... but someone has to do it. Thank you very much, testers!
At the moment, 64-bit without "test" enabled will definitely bork your install. So if user have "test/testing" enabled and updates don't go their way, that would be unfortunate.
One of my concerns is that 64-bit may take a long time to become "stable" or "production".
Although the focus of our efforts is on this architecture, be assured that i586 is also in development ... and not too far behind 64-bit ... it's actually closer than many might not believe.
We could surely use another committed user to help out.
Peace and much respect,