It's taken longer than I had hoped, but the live backing up of posts in their source form has now been pushed live. Now, every time a post gets written, a copy of the text gets sent to an offsite-backup immediately before the post is written locally. As long as the server can reach the internet, then, published posts will be backed up. The current Live Backups offsite-backup server is different than the offsite backup server which was in place since the beginning of Powerblogs. Soon we'll get that server configured for Live Backups as well, and then we'll have two offsite backups of posts separated by a few hundred miles.
This has been tested and should not have a noticeable impact on speed, but it hasn't been tested live (obviously), so during our initial experiences with it going live, there may be some delays in responsiveness in posting (on the order of about 30 seconds at the utmost maximum). If there are, please bear with us and we'll have those delays resolved quickly (but do let us know).
Update: Of course, there were timing issues. Unfortunately, they ran into the minutes, not seconds, so I've temporarily disabled the Live Backup system. I'm going to modify it to run the backup in the background so it has no chance of slowing down posting, and push it live again. With luck, that will be tonight.
Update: This is attempt two. Now the backup process runs in parallel to the posting process, so there should be no way that the Live Backups can possibly interfere with posting. It works great in testing, so I've pushed it live again. If you have any issues posting, please let us know immediately. Thanks!
Update: Ok, attempt two didn't work either. It was fast enough, but apparently sometimes interfered with the front page being rewritten after posts are published. I disabled LiveBackups again. The next version uses a completely different approach where the user interface process writes to a local process which then turns around and makes the foreign connection. The local connection will always be instant, since the same computer that you're running on can't disappear out from under you (or get lagged because some construction worker took out an internet line with a backhoe and traffic is being routed around it) unlike foreign computers, so this one should be downright foolproof. I hope to have it up tonight.
Update: Ok, here goes attempt three. As I mentioned, this one has the user interface process dumping the data off to another local process which can wait on the remote backup server without stalling the user interface or the writing of the blog pages. I've tested it very thoroughly, which means that it might work. ;)