The point of the article is that the transition to 64-bit is slow. Even if you do have a 64-bit Windows machine, most the things you run are still 32-bit.
I pray nobody runs Windows XP 64-bit Edition or Windows XP Professional x64 Edition. Those were some REAL atrocities. Both were somewhat slow since 64-bit Windows was in its infancy, and I vaguely remember hearing something about Itanium 64 having issues where the program would crash if something wasn't aligned properly. In addition, the Itanium 64 CPUs apparently had an on-board chip that decoded IA-32 (32-bit) instructions. According to Wikipedia, however, it was so slow that Microsoft created their own 32-bit to 64-bit codec for its WOW64 emulation layer to allow 32-bit applications to run properly. 
Anyway, even MS Office isn't 64-bit yet, though Office 2010 (Office 14) is supposed to be shipping both 32-bit and 64-bit builds. You can find articles all over Google about that at various sites, including reputable ones such as Ars Technica.