I believe the newest releases of Oblivion, id est the "Game of the Year Edition" and the expansion packs, has slightly more security - although I believe that they still do not ask for a CD-key or an on-line activation when you install. However, both of those games do require the DVD/CD to be within the drive when you are playing - something that I sometimes find annoying, but not enough to not buy a product that uses it*. As for Internet verification, I believe the only games that I have bought that require a one-time, on-line activation are Valve products -no, that's not quite correct, I also have two Sam and Max games that I got either as a free sample from Steam or as a gift- and I only bothered to buy them, or, rather, re-buy them, after a free version (thanks again Pop) proved that Steam was no big deal. However, it is true that Steam will allow you to re-install the games on any computer, making it very different from the system proposed for Mass Effect. Also, the fact that Valve spawned Steam tends to make potential customers more stoic about the activation - if only because they know that there will also be some benefits gained from the action. On the other hand, Mass Effect's data rights management system will do nothing but cause problems for the legal players - something that does not make one want to go out and buy the game.
*But it is nice when companies, id est Bioware with the original Neverwinter Nights' 1.68 patch, remove the requirement after a few years.