[Galaxy Tab 8.9 SGH-i957 Android Development] nrvate:
I suppose I should try to put a list together... time hasn't been my friend since i've actually had to work again.. vacation was nice!!

fail: Samsung proprietary stuff (the dock, hdmi out, any gadgets that connect to the 30pin connector)

fail: bluetooth keyboard settings, but bluetooth keyboard itself works

fail: bluetooth a2dp audio routing, although using a headset for VOIP/skype seems OK

fail: offmode charging

what else am I missing?

honestly, if you're that worried about what doesn't work, back up your ROM. If you dont like it, reboot to recovery, hit restore and go make yourself a sammich ;)

Either way, I highly recommend you do a TWRP backup anyways, so you don't have to ODIN and all that to get back to honeycomb, should you want to do such a horrible thing...

regarding the cellular data issue... I noticed the sgh-i577 (att calls it the "exhilarate" FWTW) just got an ICS ROM. With such, the latest RIL goodies for this chipset come. The i577 radio image totally borks the radio, but the RIL libraries seem to work pretty nicely with the i957 stock radio. I haven't tried them with skyrocket or note radios. IMHO, the stock radio firmware seems to works best with the CM10 note RIL libraries or these i577 RILs.

flashable zip at:

http://droid.arm.ee/957/i577ril.zip

probably best to flash it twice, as that seems to be the going recommendation.

for verification of installed files:

md5sum /system/bin/netmgrd /system/bin/ks /system/bin/qcks /system/bin/sec-ril /system/bin/qmiproxy /system/bin/qmuxd /system/bin/rmt_storage /system/bin/rild /system/lib/libsecril-client.so /system/lib/libqmi.so /system/lib/libqdi.so /system/lib/libqdp.so /system/lib/libqmiservices.so /system/lib/libqueue.so /system/lib/libril.so /system/lib/libreference-ril.so /system/lib/libril-qc-qmi-1.so /system/lib/libril-qcril-hook-oem.so /system/lib/libdsutils.so /system/lib/libdsi_netctrl.so /system/lib/libidl.so /system/lib/libnetmgr.so

b172578f5f906eaebbd2461e687c7cc2 /system/bin/netmgrd
98c2972920458d911218a54553cd3c79 /system/bin/ks
377915b8d13e82d7601d0497eb256120 /system/bin/qcks
6d3f2eb79fb1bbaa685f2a48e7fce17a /system/bin/sec-ril
267e57c65c2bff218fadab5c759dabb9 /system/bin/qmiproxy
e657f3425f58b6f13cb585ab10bc7951 /system/bin/qmuxd
36bbf6c7b6b22c68e7a1e4182f9f2aa2 /system/bin/rmt_storage
cd4344598f040df2c149d767094d07cc /system/bin/rild
02392159599f797dc2a09a483e2fe6cf /system/lib/libsecril-client.so
a26a800b7cc55fd9bad1faee88179c6e /system/lib/libqmi.so
3808c53ddc220d2f0d527072ca3326bb /system/lib/libqdi.so
ad76d61b4b81d5f5c39a76a7a826ef2a /system/lib/libqdp.so
0fe1f6a3973aa09d963901e30a28ee52 /system/lib/libqmiservices.so
253e3f0a191a8b95fdfe3b968b4a1d2a /system/lib/libqueue.so
2ab186e40ae6cd56c830c6d9d5af29b0 /system/lib/libril.so
7dd2d8f809c745e84a66f53a115a84bc /system/lib/libreference-ril.so
6be2e047bdaa49b7f15aa4234c9e8036 /system/lib/libril-qc-qmi-1.so
ad2d677eb403bd9f1b810e95c95c0565 /system/lib/libril-qcril-hook-oem.so
a961d9d5e772df615c66dbf2ab046d6e /system/lib/libdsutils.so
28536215159554125e0a8d18c4c4cad6 /system/lib/libdsi_netctrl.so
ba4a716b96cfb211d38317e108cbe83b /system/lib/libidl.so
7c04727b6adf4d9007383f87c14765fd /system/lib/libnetmgr.so