Old battlenet (before SC2) could disable CD keys in multiplayer, and was a level of DRM I'm ok with. People hack, and having a mechanism to ban them made sense. It doesn't have to come with all of the "single account tied to your purchase" or "3 hardware changes" that we're starting to see.

I'm pretty much OK with CD-keys, and I tolerate Steam because it hasn't had serious problems yet, but anything else I tend to distrust.