I have to say that i have successfully got full retail working on dell d420.
I had problems with Iatkos and everything else so i decided to try retail works great!
* Internal Mic doesn't work
* Default Intel wireless card doesn't work (I replaced with Dell wireless 1390)
*With the dell wireless 1390, every time a new upgrade (I.e 10.6.6 > 10.6.7) I have to install a kext for the computer to detect it
* Preview is broken ( I don't know why but screen shots won't work or pictures won't open)
*Intel Graphics card runs native Only down fall is instead of running it 256mb vram it runs 128mb
but it runs its full 1200 x 800 perfect out of the box
* all the internet browsers have a problem loading youtube except Firefox 3.6xx
*memory card slot doesn't work
* Of course sleep mode
And that's bout it, Blue Tooth is 100% perfect (runs better then Windows) I have the App store, Full updates and Xcode is perfect reads my full processing power and well I'm using it right now