I was asking this exact same question three weeks ago.
here's your answer.
It's not new, been around since 2005, but it came way down in price this last year and it's perfect for what i want.
So simple...
Plugs into firewire.
Open up Garageband (i use logic though...)
set the inputs for all 8 channels, on all 8 tracks (actually you can get up to 10 channels if you use something with a s/pdif like a synth or sampler, and you can also plug in a MIDI keyboard for your 10th channel)
and click record.
Mulitchannel goodness.
The drivers are so solid...I guess the engineers were Apple engineers and the drivers are built right into OS X! that's what really sold me....
So i bought this thing, went and rented some sweet drum mics for like 30 beans,
and me, my Firepod and my Macbook are a portable recording studio.
*runs off to go record...*