If you've initially installed a 32-bit OS and you expect a seamless upgrade to a 64-bit OS then it's honestly a use case that shouldn't be looked at or have resources devoted to solving.
Re:The future of Ubuntu revealed
by josephlord on Monday December 03, 2012 @09:08PM
(#4869151)
You might be right but I'm not the only person that wants to do it.
A few years ago the recommendation (on the Ubuntu site) was to install the 32bit version but now the stability and performance gains of 64bit builds make the trade off different.
The box doubles as my home MythTV box (with uptime requirements to keep my family happy) and general home server including running as a test server.
I would like it if you could run an upgrade process to switch to a 64bit install though. It seems at the moment as if a reinstall is required (or major hacking).