[TippeX]

well, sometimes developers decide to go with no protection (or possibly a simple cdcheck) after they think the sales window has passed... this is noticable in the unreal tournament updates etc... Sometimes they also remove the protection if they had a lot of claims from users about it being too strict or buggy etc...

I dont think its realistic however to assume that they'll switch from protection to authentication (online) checks in the future.. it really heavily depends on the publisher..