A way to export your own Lists in XML format or something similar. If there is one already, I do not see it.

There's an "export" button at the bottom of each of the pages under the "My Lists" tab.

I agree. It would be nice to be able to synchronize your lists here with MAL or similar sites using the XML export files (that were standardized by MAL because it had monopoly).
Someone could just build a XML<->TXT converter though, there is no real need to implement it on the website if you don't want to.

Quote from hahhah42

There's an "export" button at the bottom of each of the pages under the "My Lists" tab.

Thanks. Never spotted it before.