I was bummed about the inability to add memory, but I've discovered some pretty cool workarounds.
For one, USB mass storage is working on several of the ICS ROMS I've tried, such as Hellfire KS and my new favorite SGT7. By using a powered USB hub and an app called "Stick Mount", I've been able to mount a 32GB flash drive. Because it requires a powered hub, it's not portable, but it's still cool to have that option.
What I like even better are some software solutions I've found which let me access my media over my wifi network, eliminating the need for physical storage:
BS Player - It's a general media player which runs many audio and video formats. Put it in LAN mode and you can browse shared folders on your PC. One really cool feature is that if you play an audio file over LAN, it can automatically add all of the other files in that folder to the playlist.
X-Plore - a really well-made dual pane file browser which can access folders via LAN and FTP. This is nice for backing up large files and such. The dual pane feature makes it super easy to transfer files from one location to the other.
Anyway, I hope that's helpful.