Cheapy, "nightmare" was pretty appropriate while we were in the thick of the PS3 error thing, at the time *no one* knew what was wrong, and it looked like some sort of bug had just killed every single older PS3 model. People were envisioning worst case scenarios of mail-in fix discs, or having to send in their consoles. At the time, until they figured out the cause, *no one* knew it was only going to last 24 hours. So yeah, finding out you may own a $500-600 brick is pretty damn scary.
I don't agree with Wombat's compromise of "if you want to send the message that you don't like the DRM, don't buy the game, and don't pirate it. If you want worse DRM, don't buy it, and then pirate it." It doesn't work that way, I don't think any publisher is going to suss out the true intention of what you're doing, especially if you need to explain it and it still isn't obvious. If no one buys the game, AND no one torrents it, the publisher interprets that as zero interest and won't release another in that series. if no one buys, and everyone torrents, then obviously there's a ton of interest, but either the price point is way too high, or they're doing something else no one agrees with, and the solution is to change strategies. (To what, it really depends on how the publisher interprets those tea leaves...)
I think there are two better ways to go about this:
1. Preorder the game online, then cancel the preorder, and forward it to the publisher, telling them why you cancelled. I just did this with Yakuza 3 (for the omitted content)
2. In the case of AC2, buy the game somewhere with a good return policy, open it, and then return it saying it's unplayable because it keeps kicking you to the main menu because the DRM doesn't like your wifi connection. They can't legally resell those and must return them to the manufacturer. That sends a much clearer message.
DRM explained for console-exclusive gamers: Imagine you have an Xbox 360, and it red rings. Your friend is kind enough to loan you a 360 to finish playing through Halo ODST. You load it up, only to find out you can't play the game you purchased because it's registered to the dead 360. You call up Microsoft and explain the situation, and after taking down the new serial number of the console and putting you on hold for 2 hours, you can play the game. When your 360 comes back, you have to repeat the process.
Now, imagine that you could avoid the situation if you had just rented ODST instead of outright bought it on day 1. Which is the more appealing option? (For that matter, how is renting at all different from piracy? Those are still lost sales.)
Oh, and Wombat, if you made it to the bottom of this post, congratulations, you win a free sealed copy of Halo 3: ODST! I accidentally bought two and the second one is sitting on my shelf collecting dust.

Shoot me a PM to claim your prize.