Myke,
"The memory is all over the place" comment - is that just today or have you noticed it for the 5 days you've had 4.5? Also, there's no harm in backing up every day - it seems a little extreme but if you have a lot of activity you can't be too careful. (Did I just contradict myself? )
Regarding your "...Should it act like this so soon? It didn't do this before the upgrade." I think you may have answered your own question. It SHOULDN'T act like this but frankly, the release still has a few bugs, maybe more than "normal." It has a LOT of new features (HTML email, video camera, video streaming, etc.) that weren't available previously to many of us.
You probably know that the beta has been "obtainable" for a long while - the official releases, and they are not complete for all devices yet, have only been out a short while and we all want to keep them if we can stand the bugs. I hope that info helps - good luck and keep backing up. I don't do it often enough.