Same thing happened to me, Jim. I think they're just trying to make us look bad!
In our environment we are only fully utilizing app metering and inventory solution on the NS/CMS side. I did the upgrade to R13 this weekend and found no surprises. I had to first install R13 then install the solution updates. The only thing I really caught was the app metering configuration settings did get adjusted by the upgrade, but I took a screen shot of that page before the upgrade and was able to quickly plug my settings back in.
I think the upgrade to R13 also disables the Altiris Agent Upgrade policy as I swear I remember I left that enabled but noticed it was disabled after the upgrade.