> V8 does not actually run on any big-endian architectures [...] doesn't matter since there is not big endian support for ARM in v8

@deanm I don't understand how node could run on BE if v8 can't? Also, I created a function and returned the following:
```
return Number::New(__LITTLE_ENDIAN)  // result: 1234
return Number::New(__BIG_ENDIAN)     // result: 4321
return Number::New(__BYTE_ORDER)     // result: 1234
```
So at least on my box (Ubuntu 12.10 x64, clang v3.2 and gcc 4.7) it's defined. And in your own comments "Windows will always be little endian (including ARM)" so if `__BYTE_ORDER` is undefined then it will fail to LE by default.

I'll leave the decision to @bnoordhuis and @piscisaureus to whether keep the current implementation or use [src/v8_typed_array_bswap.h#27-31](https://github.com/deanm/node/blob/e0f81ee7cbca8e1864a0ae2544600a0fea1fb660/src/v8_typed_array_bswap.h#L27-L31). And I can't use your implementation anyways until the patch is accepted.