Alpha Protocol was originally planned to be released in October 2009, but as the release date drew ever closer, Sega decided to postpone the launch of the game and gave it a new release window of Spring 2010. Since then nothing has really been heard of the title, but Obsidian, the developer, have been hard at work making changes to the title.
The game's lighting has been considerably tweaked and there have also been a few usability changes applied to make the experience feel more natural. However, the official word from Sega (via Matthew Hickman) is that they really "wanted to polish the game up, make it everything Obsidian planned it to be, and give the consumer a very polished game."
However, as a consequence of this, Sega have decided to give Obsidian even more time to focus on producing the best title they possibly can, and perhaps to avoid some of the big guns that are coming out around the same time: Final Fantasy XIII, God of War III and Splinter Cell: Conviction to name but a few. As such, the game has been delayed again until Summer 2010 and hopefully this is the last time the game is pushed back. It would be a shame to see it delayed even further as it actually looks like quite a promising title.
Source: MTV Multiplayer