I've just finished wading through all 43 pages in this Diablo Turbo thread. First off, thank you maacruz! I've just updated my first n800 to DT. The user interface is noticeably more responsive. And many folks have expressed their thanks for fixing numerous bugs related to freezing, crashing, and reboots. Thank you maacruz!

Next up... is a rehash of the original instructions for folks wondering if they missed something important between the 1st and last pages of this thread :-) Most of the discussion in this thread was related to folks not following the directions, troubleshooting bugs which were eventually fixed, or discussing work arounds for off topic or loosely connected subjects. If you follow the following, you should be fine... [caveat emptor, backups are golden, and the usual disclaimers...]

How to install:
Pre-requisites:
rootsh: http://wiki.maemo.org/Root_access

Optional Pre-requisites: CSSU installed on top of latest Diablo firmware, Advanced systemui
Updating Firmware: http://wiki.maemo.org/Updating_the_firmware
CSSU: http://wiki.maemo.org/Diablo_Community_Project
ASUI:http://talk.maemo.org/showthread.php?t=63292

Download Diablo Turbo zImage and *.deb files from:
https://garage.maemo.org/frs/?group_id=2036
(don't download files under the sources or obsolete headers)

Create directory /media/mmc1/dt (your external SDHC card)
move all saved dt files to this location

[Verify you have at least 8 MB free]
Open filemanager, press the info button or file->details

[become root:]
start utilities, xterm
> sudo gainroot

[Repository extras-devel or CSSU repository must be enabled to install this]
(where ?? substitute 34 for N800, 44 for N810, 48 for N810-wimax)
> dpkg -r osso-software-version-rx??
> apt-get install osso-software-version-rx??-unlocked
> cd /media/mmc1/dt

[now to install all debs expect an error about sysvinit when you execute the following...]
> dpkg -i *.deb

[work around the aforementioned error by installing sysvinit again]
> dpkg -i sysvinit_2.85-22.osso15-dt1_armel.deb

[optionally, upgrade to the testing kernel]
> fiasco-flasher -f -k zImage

reboot

start utilities, xterm
> uname -a
[you should see the following...]
Linux noname 2.6.21-omap1 #2 PREEMPT [build date] armv6l unknown

enjoy...