Superuser.apk does not open.
Installer does not work on Samsung ROMs.
Factory reset (from settings menu) does not clear /datadata.
Device encryption does not work. (Note: temporarily broken again in BUILD 4, works on BUILD 5)
User does not have write permission for external sd
A2DP bluetooth headsets do not work.
Large photos cannot be edited.
Missing Live Wallpapers
Bluetooth Reverse Tether does not work
Wi-Fi Direct not supported (it's supported in settings now, but apps are needed to use it as ICS does not come with any use-case for Wi-Fi direct)
Sometimes wifi strength won't show after boot if wifi is enabled. Toggle once to fix. (fixed, hopefully)
VPN does not work
Regression in device encryption
Persistent "Removed SD card" message on external sd card removal.
Missing library for Android Open Accessory
Support for USB Mass Storage (see FAQ)
Cannot encrypt phone after restoring data.
Wi-Fi problems for Iran users
Market download temporarily goes to /datadata
Support for TV Out (in Galaxy S Setting application)
Screen appearing for a split second after screen off animation
USB Tethering on Windows requires the user go to to driver update and manually select the RNDIS driver.
Sketchy wifi tether (breaks if data connection comes up while tether is active) (it will still error, but you can now re-enable it)
Mounting external SD via USB broke in BUILD 7
Cannot accept many file types via bluetooth
Data activity icon sometimes gets stuck even data is off.
New feature: T9 Dialing by devatwork (Enable in Dialer Setting)
WPA Wifi Tethering broken (regression in BUILD 8)
Audio recording by android app crashes (phone calls still work) (regression in BUILD 8)
Phone crashes in landscape with T9 enabled
Reboot to recovery by default even though recovery not selected.
Slow T9 speed
CPU rarely scaling up to 1000 MHz
GMail sometimes fills up /datadata with attachments
No hardware composition (but hardware acceleration works)
Video recording does not work.
Video playback is not hardware-accelerated.
The front camera produces distorted preview.
Photo taking does not work with the front camera.
Some camera options FC. (The camera is a temporary hack, when the Nexus S ICS source is released, there will be a proper fix.)
Movie Studio does not work.
WiFi automatically turns on after quitting airplane mode if WiFi was used during airplane mode.
Data Roaming is enabled by default
Can select widget on launcher without being on the widget screen *
Encryption not working without a data wipe (WARNING: users with already encrypted phone will have their data cleared)
Cannot authenticate new apps for root
Data sometimes get disabled on boot
Compass, accelerometer broken in certain apps
Random force closes (hopefully)
Missing camera touch to focus (thanks to havlenapetr)
GPS does not work (regression in BUILD 11)
Off-charging does not show progress
/datadata cache not cleared when space is low
Slow mass storage transfer speed
Automatic brightness not working

720p Video Recording laggy
Camera does not support scene modes
FM Radio does not work.
Phone unnecessarily gets data connection on device encryption password enter screen.
Cannot format external SD *
Sometimes duplicates listing of external SD files in the media database
Android OS battery usage display higher than normal.
Sometime wrong SMS selected for forwarding
Format internal instead of external SD when requested to format ext. SD
Transfer speed slows down when screen off
Notification power widget uncustomizable (the widget made it into the repo, but the CMSetting app didn't.) (temporary alpha build of CMSettings)
Gallery face glow FCs
Screenshot shutter sound
No camera zoom
Camera crashes when changing resolution