predcon: Blood Omen: Legacy of Kain seems to be "poster child" material for GoG.com, but I'm wondering why it hasn't been added to the library of content yet. Is there some issue as to who has the right to the Intellectual Property and thus a licensing conflict? Or have the the head GoGites just not got around to entering a distribution agreement with whomever does, in fact, own the rights to Blood Omen?
For any given title, anyone who holds any rights to the game has to be tracked down, and all parties have to agree to allow GOG to distribute the game. Often this just means an agreement with the publisher, but sometimes different assets are owned by different people, and licensed games (for example, Sam & Max or the D&D games) pose additional troubles.
After an agreement is reached, GOG does compatibility work and QA to ensure that the game works on Windows XP and Vista. That in itself can take a while; according to a recent interview, there are some titles they've been working on for months.
Anything that hasn't been released on GOG is either somewhere in this process or on a very long to-do list, provided it's a title that they actually want to distribute. As of right now, no deal with Square-Enix has been announced, but I guarantee you that GOG is interested in acquiring Eidos' back catalogue.