What's wrong with creating a subdirectory under Drive0/Var for the purpose of installing user apps?

Potential problems:

1. /drive0/var is also where your config.ini and other Important Things (tm) live. One very human mistake in an install script or even in an installer's own code and that stuff could get torched. Not a good thing.
2. Music partitions can approach 100% capacity as new tunes are added. The reserved /dev/hda2 partition (which is currently there on *everyone's Empeg* and is not used for anything normally) would be isolated from such things.
3. Isolating the user apps to their own drive is also a good thing as people start to experiment with various ways of having read-write access to write GPS logs, ODB-2 logs, or whatever other kind of info.

Oh, and user apps were what this partition was set aside for in the first place (according to Hugo). That alone is enough for me to say let's put it to good use.

If the 2.0 final creates a new partition, then the partition would be erased with each upgrade and all the user-apps would have to be reinstalled every time somone .upgrades

That's exactly what I said it would *not* do if this were implemented the way I'm asking. My request is that the upgrade file and upgrade tool work in such a way that if the partition doesn't already exist, it gets mkfs'ed (formatted) and mounted to /usr. If it does exist, it's left alone. The upgrade files clearly already have some mechanism for doing certain things to the partitions and pumping various contents onto them, I can't imagine this is that much of a big deal?