A few quick questions

1. I am assuming that when XeTeX is updated, that it is necessary to regenerate 
XeTeX *.fmt files -- yes?

2. Thus far, I have generated a XeTeX fmt file. say xfoobar.fmt, and done:

sudo cp xfoobar.fmt /usr/local/tetex/share/texmf.local/web2c/

Is this correct? Is there anything else I should be doing?

3. Is there some place I can put xfoobar.fmt (or something I can do) to prevent 
it from being clobbered when I update TeX using the i-Installer?

Thanks for any illumination.

SGM