The requirements on GOG are a bit off/high. I run this game on my 2010 MacBook Air 11" just fine.

OS X Snow Leopard 10.6.8
1.4Ghz Core 2 Duo Processor (running single core at about 46% cpu)
2GB Memory (uses about 450+ memory)
Nvidia 320M 256MB (GOG states lower on this, 128MB)
298MB Hard Disk Space
OpenGL 2.1

This game is also wrapped. Wish it would have been native code and actually compiled on OS X. Anyway, it does run smooth. Cpu doesn't spike like crazy and stutter.

Thanks, may give it a try on my mbp, which I'm keeping at 10.7 for the foreseeable future.

I didn't want to have to explain mono if anyone asked, so I just said it's wrapped. Either way, it's not native code. It still uses Windows/Microsoft binaries. It does run pretty smooth though. ;)

Well, no, it doesn't use Windows/Microsoft binaries. It uses Mono for scripting, and native code. As I said, similar to Unity; most engines use some kind of JIT or interpreted scripting on top of the core but that doesn't make them not native. The dlls included in Terraria are CIL code and not Windows binaries. The included dylib files are quite native.

Theoretically the performance could be improved by writing the entire thing in straight C++, but that applies equally to the Windows version. It also applies to thousands of other games. The idea of having scripting in an engine is that you take a minor hit to performance as a tradeoff for increased productivity. A lot of times the bottleneck is the GPU rather than the CPU anyway. Terraria runs more than fast enough as it is (taking a small fraction of the available CPU power on my 4-core machine), so writing the whole thing in C++ would gain nothing. (Well, perhaps slightly better battery life if you play a lot on a laptop.)

Anyway! Technical details aside, the point is not to scare anyone away by claiming it's something that it's not. It's no more wrapped than the Windows version is, and is nothing like the often-problematic Cider-wrapped "Mac versions" of some other games that have been published. (Although, to be fair, apparently the Windows version of Terraria does run well wrapped in WINE, but I held off on that since hearing rumors of a proper Mac version.)

I really didn't want to get into a topic about this but I've been writing and compiling software well over a decade. Mono translates ECMA CIL byte code into native code. Therefor, it is not native code and slightly slower. I personally don't know why anyone would want to use a runtime such as .Net or Java but that's me. The further we get away from just compiling native code, the slower and bulkier our apps will be.

I was not trying to deter anyone from the game. It runs fine on modern hardware. Please don't get me started on Unity. It needs optimized. I don't recommend game maker apps. Just write and compile your own code.