It's more of a worst case thing is the reason I don't want to use SQLite. If you're in a position that the only way to recover your data is through means of using some text editor, and only that, the SQLite data is basically GONE! Any binary format will be in that position actually.
And in the case of extensions, the browser does need to support it. (BTW, wrong thread to hijack for this discussion, wrong section)
And then there's the whole needing a RDF to SQLite conversion. An RDF to random XML format is more likely to work without issues (XSL).