The message in calibre is nothing more than a warning; Tim added in a check on the version info in the database.
I can assure you that I have had no issues with calibre and Touch 2.0.
And in fact if anyone bothers to look at the
code, it uses the exact same database update commands for 0.8.57 and the newer 0.8.58; all you have to do is enable the writing option.