On the dell linux mailing list, I asked:
Several people have posted how-to articles for installing the "standard" version of Hardy or Intrepid on the Mini (like the Ubuntu wiki article: https://help.ubuntu.com/community/DellMini9 ). If I understand correctly, this leaves them with the i386 kernel, not the LPIA version. What exactly are the advantages of the LPIA version? Better performance? Battery life? Is the difference enough to care about?
Here's an answer I got from Mario at Dell, who (I think) is their primary Ubuntu engineer: http://lists.us.dell.com/pipermail/l...er/002131.html
There's a few ways for this to be answered. The first part to the more
technical answer is you are supposed to be getting better performance
with the lpia kernel as the Mini9 has an Intel Atom processor. Running
the lpia kernel you will also be able to run all the packages built for
lpia. Meaning[ful]ly different compile time optimizations are chosen for
lpia packages. The second part of the technical answer is that any
kernel patches that were added to support the mini 9 may have not
necessarily landed directly in Hardy as SRUs. I know some of them did
(such as the networking bug that you see from a vanilla 8.04 that is now
fixed in 8.04.1).
Here's some examples that probably didn't land in as SRU's yet.
http://kernel.ubuntu.com/git?p=mid-team ... 032bfcdb96
http://kernel.ubuntu.com/git?p=mid-team ... a3e7b4a75d
Now the less technical answer is that you won't have "formal" support if
you are running an entirely different kernel. I know there are some
interactions with /dev/rtc that can cause kernel panics, and those might
not be fixed in hardy mainline either.
I guess door number three is the"standard" Ubuntu LPIA port http://cdimage.ubuntu.com/ports/daily/current/
which would give you the optimization benefits of using the most appropriate kernel, but you'd have to wait for any Mini-specific fixes to filter up through the maintainers. Note that I tried that image this weekend and the installer didn't leave my Mini in a bootable state, so it may just not be ready for use yet.