Riley, lead playtester for Zombie Panic: Source, and the infamous No More Room in Hell, e-mailed Robin Walker, asking him if going premium within TF2 would give you access to the Source SDK. Robin replied with this e-mail, stating that:
Yep. That said, your email has triggered a process here that made us re-examine that, and we’re going to just go ahead and make the Source SDK freely available. Thanks for making us better!
Riley shared the e-mail with the fine folks at Reddit, and they’ve went ahead and created a handy little list of mods that are worth checking out. Rock, Paper, Shotgun asked Robin about it themselves, and he did confirm it:
We are in the process of getting it all done. It’s a bit messy because we have multiple versions of the SDK, and there’s some dependencies we need to shake out. But yes, the gist of it is that we’re just going to go ahead and make the Source SDK freely available.
So, that’s great. It’s too early for any guesses, but we’re really hoping this release sports some new tools, source code for the Source 2009 build (which includes Mac support), and is compatible with all Source mods, past, present and future.
Updated: James “Echo” Pizzurro has also informed us that the SDK and both SDK Bases were made completely free yesterday, without the prerequisite of owning any Steam game on your account, so it would seem that Valve has begun this process earlier than we thought. We’d like to thank him for letting us know.