If you're a Mac user, you may not know about Steam. By Valve (makers of Half-Life and L4D) it's the greatest game distribution service in existence—like an iTunes for PC games. Now, it could be coming to Macs.
In Steam's latest beta release, a search through its files revealed a number of OSX-specific assets, like a Steam dock icon (among loads of others). Since there's no reason for OSX resources—that I should add, are specifically labeled "OSX"—to make their way into a PC product, it seems pretty certain that, yes, Steam is coming to Mac. Hooray!