Aliasing

So what's that new QuickTime 7 codec called again?

It's not an easy question. Apple mostly refers to it as "H.264", but you can also find references on Apple's website to "AVC" or "MPEG-4 Part 10". It's all the same thing.

As if that wasn't bad enough, Apple's developers use another name! If you manage to crash the H.264 decoder with your experimentation (like I did), you might see this:

Thread 7 Crashed:
0   QuickTimeH264.altivec          	0x99e35c60 JVTLibDecoDispose + 175184
1   QuickTimeH264.altivec          	0x99e35990 JVTLibDecoDispose + 174464
2   QuickTimeH264.altivec          	0x99e1a454 JVTLibDecoDispose + 62532
3   QuickTimeH264.altivec          	0x99e0a9b0 JVTCompEndPass + 17972
4   QuickTimeH264.altivec          	0x99e0a250 JVTCompEndPass + 16084
5   QuickTimeH264.altivec          	0x99e32cf0 JVTLibDecoDispose + 163040
6   QuickTimeH264.altivec          	0x99e32c34 JVTLibDecoDispose + 162852
7   libSystem.B.dylib              	0x9002c3d4 _pthread_body + 96

Apple's developers still call it the JVT codec, for "Joint Video Team". You can find more on the naming confusion at Wikipedia.