The demo UI won't let you specify various resolutions that fit (say) a 23"
Cinema Display well. This is because the list of available resolutions are
hardcoded in UnrealScript and changing this breaks network compatibility with
Linux and Windows players. I snuck all the popular Mac screen resolutions
(like 1680x1050 and 1920x1200) in before the latest win32 patch, so the
retail Mac version will have these out of the box. The brave among you can
get the demo to use these resolutions by editing a config file; otherwise,
you can use the in-game UI for the price of the game.
There are Altivec optimizations if you've got a G4 CPU, but this isn't
required (game runs on G3s for you poor bastards that are in iBook land).
The game does use dual CPUs...the music is decoded in a separate thread
which MacOS X will toss on the second processor on dual systems. Some
implementations of OpenAL will do their mixing on the second processor, too.
On Linux, this is easily a 5-10 fps boost for SMP boxes, and I wouldn't be
surprised to see similar results on the Mac...but I haven't explicitly
benchmarked this. Most games are generally single-threaded, but understand
that this means a Dual box will still be able to cook one CPU for the game
itself and run the other 20 or so system processes on the other processor,
so there's still a benefit to this.