Yes, for a Unix sysadmin I'm sure exporting your content via Tumblr's API, RSS feed or for that matter a Wordpress utility is a breeze but I'm not sure the same

Yes, for a Unix sysadmin I'm sure exporting your content via Tumblr's API, RSS feed or for that matter a Wordpress utility is a breeze but I'm not sure the same is true for your average tumblr user. Having said all that I think you're ignoring what I said for the sake of an argument.