Embarrassments I get in first day with Mac Mountain Lion

As a Mac user jumping from Snow Leopard to Mountain Lion, there is much for me to catch up. 
First at all, the direction of scroll operation has been totally reversed in Lion, it is surprise to find that moving fingers down on the trackpad leads to the scroll up of the current content, not the scroll down as before and all other desktop OSes. According to one book about Mac Lion, here, Apple intends to provide the same user experience on Mac as the iPhone and iPad, sure, we scroll content directly on iOS devices, in fact, on Mac OS before Lion and all other desktop OSes, we scroll the viewable frame, which is indicated by the scroll bar, not the content. Reasonable? Anyway, I prefer the consistent user experience with iOS device, so I will try sticking to the new way. 
The second funny thing is that after I shutdown Mount Lion first time, as I always do, I use one small application docked in Mac's doc, then there is problem, every time, I boot up system, it will show me a desktop and shutdown immediately. For about 2 minutes, I am totally scared because my MBP is also a production system for me, then I think... and find the root cause. By default, from Lion, OS X will restore all the applications, which were running in the last shutdown, when user log in back, here, the shutdown application is started. I find a hack method to salvage my MBP, I log in as another user, then in that user's desktop I switch to my main account, in this case, because there is already one active user, that shutdown application gives me a dialog to confirm that I need to kick off that user, then I press "cancel" button and finally get the chance to use my main account's desktop. I prefer to try Lion's application restore in login feature, so I remove that shutdown application to avoid problem in the future. 

I think it is a good decision to transfer to a new version of OS X during my PTO days.