I will say I don't like it for online storage of any kind, but it's pretty hard to beat XML as an offline interchange or archival format. Case in point: we can

I will say I don't like it for online storage of any kind, but it's pretty hard to beat XML as an offline interchange or archival format. Case in point: we can dump an entire client's data from our system into a single gzipped XML blob straight from the ORM. This can also be restored straight back into the ORM as well with very little code. This means we can switch database engines, do snapshots, backups, manage on site deployments and all sorts of nice things very easily.