Hmm... interesting idea.
I also bought my copy of Spacemarine one day early, but that was totally ok, as Steam wouldn't allow you to install the game until it was released. Wasn't a big deal for me, as I litterally installed it the minute it went live here in europe. I think the "nasty surprise" Is a fair way to keep everybody playing by the same rules. If it's sheduled for release on a specific day then you just don't get to play before that. They could have gone the MS-live approach and just lock down your account for breaking the rules, but this seems quite fair inmo.
It's definitly not the first "hidden DRM" though. Settlers 2 was designed in a way that it could detect if you installed the game from a legit source or a burned CD (back in the days of yore where CD images where a pipedream at best). If it concluded that you pirated the game, it literally broke your economy by having select buildings freak out and producing absolutly useless sheep.
On the other hand, Titanquest suffered from it's hidden DRM - when entering or exiting a dungeon it could suddenly freeze if it detected a crack or bad DVD as part of it's security check. As it gave no reason for the freeze, the reviews plummeted as faggy pirates dared to complain about their broken games.
I suppose the always on DRM would be in the PC version of the game, as it's currently all the rage to bend over your customers and shoving glowing hot steel I-beams up their rear for daring to support legit purchases.
The whole DRM business has ruined many of my favorite series - most notably Heroes of Might and Magic and possibly even Diablo 3.
Let's suffice to say that pirated versions without the DRM will propably not notice unless they are stupid enough to actually play online.