The Mac computer mouse is useless get yourself a pc mouse.
This is a matter of personal preference, but yes, most people hate the Magic Mouse. I use a gamer mouse, and plan to also use Apple's Magic Trackpad for the gesture interface and general use.
Then you have to pay more money for the same parts as intel.
Yes, it's true. You could buy the same components and put them in an inferior case and hook them up to an inferior monitor for less money. Whether you want to pay the so-called "Apple Tax" really depends on how important build quality and display quality is to you.
Do you play games? not all games run on Mac.
Yes they will. Not all run on OS X at launch though. There are games where you will need to wait for an OS X port, or if one isn't coming, set up a Bootcamp partition so you can run them in Windows.
There is not much virus but it will be more in the future when more people start to use the Mac.
When you use the term "virus" as it's actually defined for computer programs, there are zero for the Mac. There are a tiny number of malware programs, all of which are "trojan horses" that basically require the user to do something stupid to run them, and all of them are cleaned & prevented by the latest OS X patches. I expect this trend to continue. (There is, as I recall, one that required less user action, but that was a universal Java problem and affected OS X equally as Windows.)
I'm actually not sure what your purpose was in posting. The OP was asking about the hardest thing to adjust to when switching, and it seems like you were trying to spread some FUD to talk him out of it.
----------
I'm confused by what seem like inconsistencies in how the "green" button (beside the red and yellow ones on each active window) works. In iTunes it minimizes, in Safari I think it maximized last time I tried. A minor nuisance.
The Green button is basically both "Maximize" and "Restore". "Maximize" may also elect not to fill the entire screen if the application doesn't think it needs it.