The phone is not without problems. Everyone mentioned my voice sounds a little tinny compared to on my OG Droid, and Ubuntu won't recognize the phone so music transfer is a problem. Still, I think I'll be keeping it, even if it is unbelievably huge.
The Nexus unified the filesystem, and therefore cant give USB block-level access. MTP was the only way to go unless you want to have a separate partition, which leads to the terrible 'is the app on local or on sd?' situation.
Here is the situation described: http://www.electronista.com/articles/11/11/19/galaxy.nexus.f...
For mac users, you want this tool: http://www.android.com/filetransfer/
After having the Galaxy Nexus for 2 weeks, the phone no longer feels large in my hands, but the Nexus S it replaced looks ancient and pathetically tiny/low-resolution.
I found this gadget, which is a fuse wrapper around libmtp: http://www.adebenham.com/mtpfs/
It's not packaged (though libmtp is on fedora 16 at least), but is trivially buildable and installs just a single binary. Then "mtpfs /local/mount/dir" will mount your phone's /data partition for you. Much cleaner than trying to sync via a media player IMHO.
The article you linked to explains that in the fourth paragraph. Their reasoning is that they don't want people to need a file manager in Android. It makes since to me.I like that they are going to a one large internal storage location.
Something weird is going on here, and it's likely a problem with MTP handling in Ubuntu. I've never had this trouble with other MTP devices.