the multi-button mouses do have their benefits, try playing unreal tournament, warcraft 3, or any game with one button.
i use my computer, and i prefer to only have one hand at the computer, while another flips the pages, holds a cup of juice, etc. and usually i have to hold the mouse instead of the keyboard, so, i would need a multibutton mouse to be more productive. imagine a person that has one hand occupied with reading a book or drinking while the other hand has one buttoned mouse. if he wants to access the menus, he has to go up the the menubar, and select something, then go back to where he was.
the mouses go from multibutton and one buttoned mouses being the same at productivity to having multibutton mouses better to use. there isn't much I can sacrafice when migrating from single button mouses to multibutton mouses (especially logitech's), and they are generally more versatile.
now, intel does not equal PC (windows computers), and switching to them will change macs only to better machines. there is nothing sacrificed.
now, that is different from runing windows on intel macs and macosx on traditional PC boxes. i hate that idea. ew...
people that say that intel macs and PCs are the same is like saying that rulers and a pens are the same just because they use plastic. it's also like saying that both ppc macs and intel pcs are the same just because it uses electricity and has silicone and metal.