Can I use 64-bit Ubuntu instead of 32-bit with the XBMCBuntu installer?

Is it possible to install 64-bit Ubuntu instead of 32-bit when using the XBMCBuntu installer?

Also, I'm just curious, but does XBMC automatically restart if it crashes when running XBMCBuntu?

Thanks!

EDIT: Actually, is it worth it to run under 64-bit? (I'm only using 2.0 GB of RAM, but all of my other system are 64-bit, so....)