I posted the update from user kthrash onto my new '08 Jeep Liberty. I was skeptical at first being that it isn't on any official jeep or chrysler sites, but it works like a charm. Total update time took around 7-10 minutes. The menus are definitely snappier after the update (even if you aren't an iPhone user I would recommend the update).
I burned the files to a TDK music CD-R at 4X speed on my Powerbook G4. I named the CD "NTG4_9.561", and put the three files/folders from the unzipped download onto the CD. Total size of the data on the CD was around 575 MB
The update will go through two stages, a first stage that has 2 installation progress bars, and it does pause for 10-20 seconds from time to time. The other stage of the update has the look and feel of the mygig screens, and takes only a minute or so to progress through. Afterwards the system reboots, and it took a while for the CD to eject after I pressed the button (10-20 seconds), but eventually it came out.
iPhone works flawlessly now, shows name/phone number info, battery life left, etc... It's a really sharp system. Thanks kthrash, it was a huge help.