Ok, scratch that. Everything worked fine for about a day... until I noticed apps not working correctly (not saving data & settings, can't write to files on external SD card). I also noticed that the "/external1" folder is no longer visible from the root (using Root Explorer). But if I go through "/mnt/external1" I can see everything still on the SD card. I don't think it was that way before these latest updates. In any case, my movies on SD card are also not playing, and photos not showing. Titanium Backup is not showing any of my backups (but I can see they are physically on the SD card). What in the world could have screwed all this up? The only thing I installed after these updates was the latest Netflix streaming app (v1.4.1), which worked great, so I don't think that messed anything up. It just seems like the SD card support is trashed or something.
So, now I have tried:
1. swapping & reformatting SD cards -- no luck.
2. wiping cache via CWR -- no luck.
3. Fixed permissions via CWR -- no luck.
4. re-rooting (using Universal Xoom Root) -- no luck.
I just don't know what to try next. If I just flash the latest Tiamat kernel, do you think that would solve everything??