Seriously .. thank you for this thread and for all the support you've given since you started it. Really awesome.
I ended up here because I stumbled my way into a mess when I attempted to follow some guide to root that involved editing the /system/mount_ext3.sh. Something went wrong and I couldn't get past the big red M splash screen. I could get RSD lite to see the phone, but I couldn't figure out how to get ADB to see the phone in fastboot .. maybe it's not supposed to. Anyway, another friendly fellow recommended I give this a try so I did (sort of). Here's what happened..
Since my phone was not bootable, I started from the fastboot screen and ran everything from there. All was grand until I got to the part where I boot into recovery and apply the updates from the SD card. I either missed those parts of the nistructions, or because my phone was not bootable, getting the updates onto the sd card didn't work. So I powered down, pulled the battery, put my sd card into a friends phone, moved the updates to the sd card and went back into recovery mode to apply the updates. For some reason the recovery mode wouldn't mount the sd card and I was not able to apply the updates. I don't know what's up with that.
I rebooted the phone and lo and behold the phone booted up just fine. I'm 5.9.902_XT875, no data lost. Thank you Samuri!
It does seem a tad glitchy .. the Google Play process has been force closed several times .. and the screen has flickered once or twice as though some message were flashed for a nanosecond.
Given the process didn't run as expected .. probably because I messed it up and started from an unknown state, what would you recommend I do from here?