for the "switch" from a PC to a Mac, the action is really simple... you can simply take your hard-drive and put it in your mac if you have a Mac Pro... if you have a iMac, you have to link your PC to your Mac via Ethernet, and you transfer your data...

it is simple as it is... i've done like 25 switch just these last 6 months for clients willing to change to Mac. (remember i'm a Apple Genius)

i have an old Mac Pro at home... 3 years old... 2x 2.5Ghz with 1.5Gigs Ram... and i can work Photoshop CS3 flawlessly, BBEdit with documents like 10 Mb in size, playing iTunes music in FLAC (remember that expensive format), having a webchat discussion with my niece (ya know, girls in teenage are always talking too much), Firefox with 5 to 20 tabs, Adiumx connected to (msn, yahoo, aim, icq, aol, gtalk and some others at the same time - i have a lot of clients), and actually running my webserver (Apache 2 with PHP 5 and Mysql 5... etc!) with something like 5000 hits per min., (with 7 vBulletin boards running full power!)... oh, and my wife use my Power PC to play her games from the iMac terminal... so Wolfenstein ET or Scrabbles are always runing in backtasks...

you can't do that with Windows or anyother PC!... not at the same time at least.. lol

EDIT: and if you continue to need to run some Windows APPS, you can activate Apple BootCamp so your Windows is still alive in your computer... actually on my old 3 years old mac i have Windows Vista™ in the background (SoftPC) running 2 times faster than on a Dell Dimension...

oh.. and most of the great games released lately for PC are also on Mac... and more are to be released on Mac before PC (Starcraft II will be on mac months before on PC!)