hedwards: I'll let you know how annoyed I am when I can't use my Steam powered games because I don't have access to the internet.
Even being online is not necessarily enough. I have a speedy internet connection right now, and still Steam doesn't work. Reason being, Valve does not allow proxy servers, which are mandatory in many networks all over the world. GOG games I can purchase, download and even play just fine through the same network. Ok, GOG Downloader does not seem to work (at least the last time I tried it from behind a proxy), but it is optional anyway, and it seems some 3rd party GOG downloaders are more advanced anyway.
But I agree with the previous writer that definitely there are worse DRM methods than Steam, a bit like having genital herpes is preferable to lung cancer (or so I've heard).
Anyway, even that cannot be much of praise because Valve constantly allows publishers to add third-party DRM on top of Steam DRM, including HW lock-in, installation caps etc. I might have a bit more respect for Valve if they didn't allow that, just like GOG does not allow any (extra) DRM. Currently Steam gives you only genital herpes by default, but you get lung cancer as an extra from many non-Valve games that Steam offers.
If GOG acted like Valve/Steam, they would claim to be DRM-free, while at the same time allowing Electronic Arts, Ubisoft etc. to use third party DRM in their GOG releases.