Only 5 days ago, there was a change to the Black Mesa mod site, showing a CRT television at the top of the website. When clicking on it, it would take you to the Black Mesa Research Facility website, which showed a countdown leading up to today, with some television static behind it, and the occasional, brief appearance of G-Man for a second or two.
The 5th of May is an important date in the series, for it is the original date that Gordon Freeman received his letter from the Black Mesa Office of the Administrator's LM confirming that he has been hired. It only made sense to release some very big and important news on this date. If you revisit the BMRF website now, we're left with a very pleasant surprise. We get to watch a quick video, which then ends and redirects you to the Steam page for the game.
However, Black Mesa is currently in Early-Access, meaning that it is not yet complete. In their notes on the page, they've said:
“We currently have the first ~85% of our single player campaign completed. For the last 15% we want to not only recreate it, but improve upon it to make it an enjoyable and memorable experience. We feel it will take us considerable time to get the last 15% up to our standards, and putting a time estimate on it would be a total guess.”
They've also said that there are currently 10 hours worth of the single player campaign so far, with more to come in the future once the game is out of Early-Access, such as polishing, and multiplayer modes and maps. The Early-Access price is $19.99, but it could go up in the future once the game is complete.
If you're wallet is hurting a little bit at the moment, you can still play the free mod. The free version will of course be lacking things that the Early-Access version will include.
(For those of you who aren't happy with the decision of the developers selling the game, they've addressed that here.)