With all due respect to the YOTD team, that article was in 2001. With the explosion in net access, the cracking scene is very different now, and with the criminal aspect permeating it, for the worse.
Crackers have cracked most mechanisms out there for any game with strong stand-alone presence, within days in the worst-case scenario. The more popular the game, the faster it will be fully cracked. Downloadable content doesn't stop them. Sims 3 content packs were available on the net within hours! For AA and AAA titles, they actually sometimes have people and/or systems "on the inside" getting them early copies to get a head start. I've seen big titles released in cracked form before they even hit retail! In fact, the race is on to get your cracked version out first, with trojans, so as to get the most systems.
The only copying you can deter is casual copying, and for that you don't need much. I'd look for canned systems (ex: Silicon Realms' products) and not waste my time and resources on developing my own "new and improved" scheme that will just as likely fail. Also, don't get seduced by promises of far-reaching DRM. You pay a lot for not much gain.
Yet, you should still have accommodations that allows a handful of installs for homes with multiple systems, or people that frequently change systems, or that are not online all the time. AticAtac's mechanism is an example of bad idea for people who aren't online all the time. Nothing I hate more than being stuck somewhere with bad connections and not being able to take a break with game X because of some online requirement. Not only do I end up hating the game, I likely won't buy again from that vendor...
Also, if you develop your own canned solution, don't forget to keep in mind the ignorant end-users. Lots of people may end up with a cracked game without knowing it. If you make a game behave erratically or do something damaging, they will blame you, not the cracker. Worse yet, a class action suit...
Most people who torrent casually frequently infect their systems and render them inoperable, so they eventually get what they deserve and hopefully learn from it.
Those who are veterans are armed with some intelligence and are pretty much unstoppable, because they are plugged into how and from who to download their warez.