I have some serious concerns about this interpretation of portable install files as DRM-free. As far as I understand it, the installation is a critical part of a program, as in, if you cannot install it you cannot use it, or, at least, use it properly. Some have already mentioned problems with specific titles, for instance. On the other hand, you can hardly speak about installations on flash games, so maybe those do count as DRM-free? But other than that, I consider the ability to install a game a necessary guaranty to consider it DRM-free.
Additionally, another topic that does not receive discussion enough is that of multiplayer functionalities. For me, if the game does not include a complete server client, it is DRM, because you depend on someone to play all the functionalities of the game. For example, if there is a scoreboard, and that scoreboard can only be setup by Steam or by the publisher behind the title, that is a functionality the player cannot use by her/himself (by setting up a server for a group of friends to host the scoreboard, for instance).
Post edited September 24, 2012 by MichaelPalin