Originally Black Mesa, a Half-Life remake using the Source engine, was supposed to be released at the end of 2009, but the development team underestimated the work that was still to be done. Ever since then news and updates about the Source-Mod have been rare and rather small. Now it seems like the project is slowly heading towards its end.
Lead designer Daniel "Raminator" Junek posted some interesting statistics in to Black Mesa's forum.
I bet Black Mesa ill be released UNTIL THE END OF 2012.The only chapters left are Interloper and Nihilanth, a friend saw on their forum.But this was a year ago, so I think only nihilanth might be left, but still I bet it will be released until the end of 2012.