I'm sorry for the inconvenience this is causing - here's what's going on.
When a new build of OmniFocus starts up and sees that it's newer than the build that last touched your data, the first thing it does is run through your database and look for errors in all the data that's been added since your last update. (Or the last time you backed up.)
It sounds like it just had been a quite while since this process had been run on webalstrom's machine and it took us some time to validate the data. If this happens to you, don't force-quit the app; terminating the process early could actually introduce problems where there weren't any before.
webalstrom - could you explain what you meant by 'revert to backup didn't work' in your post?
For viksolem, it sounds like we are actually having trouble reading one of your transaction files off of the disk. You'll want to contact our support ninjas at
omnifocus@omnigroup.com
so they can help you.