Ok. New problem. I downloaded the FX 3.1 update (torrent). Followed these directions (below).. and now after the reboot it says "program application database can't be found." Need some help here. Thanks!
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Okay so what I've done is simple, I took what I considered to be the basic mods that would be appealing to almost everyone, without drastically changing the look and feel of the system.
This download contains:
Windows CE 6 firmware
X Series 3.0201 update
Complete TA 2009.6 Map Upgrade (USA & Canada)
No nag screens
POI Branding
Speed camera/red light mod
Software speed bypass
You need only a single SD card, at least 2gb in size. Copy the entire contents of the RAR file to the root of SD card.
1. Insert SD card into AVIC and turn it on.
2. When the pioneer logo comes up, press and hold the menu, map, eject and the reset buttons at the same time. When you hear a pop sound from your speakers, let go of the eject button but continue to hold menu, map, and eject buttons. This will bring you to a blue screen, telling you to reset the unit (ignore this), you will have to enter the service combination. Press the volume knob in this sequence and you will see * signs for each push: Up, Up, Down, Menu, Left, Right.
3. Select Wince Upgrade
4. Select Update SD Format
5. Wait until it says restart in the bottom center. Reset the unit and leave the SD card in.
6. You should be greeted with testmode (It will look very similar to normal windows). Open Explorer and copy the contents of the "My Flash Drive" Folder from the SD card to the "My Flash Drive" that is located on the unit. Overwrite everything. (It will the copying will take 140min but will only take about 20)
7. Press and hold reset for 5 seconds.
8. Select your language and voice options.
9. Enjoy FX3.1 
Tested on AVIC-f90bt. 05/08/10