When i switched, the first thing i noticed was how user friendly it was. Setting up windows is a major job compared to setting up the Mac. Your home screen has most of the apps you would run right there. if not just get to the application folder and all you have are icons of the apps you have. There aren't folders and sub folder and program files, and this and that to run an application. Its all hidden from the user. Why confuse the user?
Your Wi-fi is set up on first boot, and that becomes your preferred network. Even setting up ethernet connection is easy...you dont have to choose network adapter and then choose properties, and then select tcp/ip or anything. just plug in an IP if you have it, or make a PPPoE straight away.
setting up windows mail is again a drag...all the year i used windows, i never used Mail, or Msn messenger, or outlook. Apple Mail on the other hand was an instant hit! opened it, put in my account details(username, pass, whether gmail or other) and it was done. i began downloading mail in a jiffy.
Using iPhoto(comes with all new macs..part of iLife) is just so easy. Its just as good as picasa, or maybe better. The most helpful tool i found on the mac was a dictionary application. No matter where you are typing( web pages, im clients, mail, calendar) or reading wikipedia, google, blogs....you can right click on a word and do look up in dictionary.
Apart from these you have stacks, on the dock you have the documents and downloads folder. Click to see what files are in there. they have improved it in snow leopard. spotlight is the mac wide search for within contents, and filenames, its on the top bar of the screen. an added feature(very handy at times) is if you use the spotlight for math it runs in calc and solves it right there for you.
Removing applications is again not a problem...as you just have to move it to trash just like any other file. no add/remove programs.
Apart from all the software awesomeness, you have the hardware. Its just more advanced than most other computers at its priced, (unless of course you go out and assemble one yourself) most computers today ship with DDR2, mac comes with DDR3 Ram(faster). Nvidia 9300, brilliant screen, very space saving dvd slot(not tray, so no need to move clutter near the computer to use
) you have the great camera, superb keyboard, and the trackpad(on notebooks) is just amazing. After using this trackpad, i hate touching the one i have on a sony!
one finger the mouse moves, 2 fingers you scroll, three fingers you scroll through pictures, and four fingers sideways on the pad is like ALT+TAB on windows, and top to bottom is to clear clutter and show all windows on your desktop and bottom to top is to move all clutter and show desktop!
I love my mac for these and many more reasons, many of which are for more experienced users(for eg. you can change the MAC ID of your ethernet card). but i hope this is compelling enough for you to move to a mac soon
PS: very few viruses!
no registry, no dlls, doesnt run exes.