Mac gamers will have a big reason to celebrate in April, as Valve has confirmed that it will be bringing the Steam software distribution platform to the Mac world. That is not all, as Valve will also be releasing Left 4 Dead, Left 4 Dead 2, Portal and Team Fortress 2, as well for the Mac platform.

The decision to add Mac support indicates a change in strategy going forward. With the addition of Mac, new titles will see release on both the PC as well as the Xbox 360 at the same time as the Mac release. The addition of Mac support included a significant overhaul of the Steam platform as well as the engine. The Steam platform will offer the same features as the counterpart on the PC/Windows platform and Mac and PC/Windows users will be able to interact and play some games together despite being on different platforms.

As we told you previously, our sources had indicated that the possibility of a Mac release looked to be in the works and with this announcement, Valve opens a new market for distribution through Steam. With its release in April, Valve will be looking to see what can be done in the Apple gaming market which has always lagged behind the PC/Windows platform for gaming despite a number of major releases to support the platform. The move could help grow the Mac gaming space in general, as the latest Mac systems feature much more robust graphics necessary for gaming than previous Mac offerings.

The more interesting thing is how much attention Steam will be able to attract from third-party publishers that wish to distribute their Mac gaming titles through Steam. If it proves popular, Steam could very quickly become the gaming distribution platform of choice for gaming on the Mac, but only if Valve is able to quickly gain third-party Mac publisher support.