Originally Posted by petercreasey
I've been waiting for Calibre 7.x to mellow a bit before upgrading my Windows XP Pro with Sony 505.
Is now a good (read: safe) time/version to upgrade from 6.x to 7.x?
Nothing in life is safe
If you are in no hurry, a few last known bugs will be ironed out in 0.7.3. Note that the version number in Calibre is not yet up to version 1 - it's still in version 0 and is very much an active work in progress, with changes being made almost every day.
That said, there is no reason to think you will be risking anything if you upgrade now. If you want any of the newer features, and there are a lot of them, I'd upgrade. You should always have a backup either way.