FYI, I am and have been a Mac user for as far back as I can remember (Mac Plus 128k!) and PPRuNe was concieved and and is still run from my Mac (G4 384Mb). PPRuNe Towers has finally been converted by the evanglisers opf the Mac and now uses his new iBook for his PPRuNe duties.
Having watched Windows mature from DROSS into its latest incarnation I can but only pity those who still live by the argument that Mac doesn't have the range of software available for it. Unless you are involved in some incredibly complex task involving nuclear reactors or obscure scientific equipment and even then I would question it, ther is no reason not to use a Mac.
You pay more initially but you get quality and by the time you add on the included features of a Mac to a PC you end up having paid the same if not more for a lower quality system.
Not being sponsored to write this but as you can tell I do like the Mac and refuse to be a PC conformist just because everybody else has one mindset! Off soapbox.