My Videonics switcher/mixer died -- we have a MacBook with FCP5.1, but I'm not sure if a Mac can handle more than one FW camera at a time. (The MacBook is used elsewhere during the week -- they bring it to the church on Sundays for editing)

Can FCP switch between two FW cams? If possible, I'd like to do the multi-clip setup, and simply click between the wideangle and zoom cams. Only two, no more.

Would I need to get a firewire expansion PCCard? I know daisy-chaining both cameras onto the same FW port won't work -- even when set to 'non-controllable device', FW can only address one camera on the bus (ok, I could be wrong about this, maybe it's been updated, I dunno) but did they make OS X able to address a second FW bus? I've never seen a Mac with more than just one -- two FW 400 ports on one bus, I mean...

We need to switch LIVE, because 1) the Canon XL1s don't support running timecode, and 2) syncing the two cams up in post takes WAY too long, even with a clapboard or pulse.

You cannot connect more than one camera at a time in FCP for direct capture, and you'll be overtaxing the resources on a Macbook running just one as it is.

"Multi-cam" is not a live-capture function, it's for post-editing only. The only way to get multi-cam live capture is with a switcher going into your NLE.

syncing the two cams up in post takes WAY too long, even with a clapboard or pulse.

Huh? How long is "WAY too long"? What exactly are you shooting with two cameras and how are you shooting it that causes the syncing process to take longer than a few seconds?

You cannot connect more than one camera at a time in FCP for direct capture, and you'll be overtaxing the resources on a Macbook running just one as it is.

"Multi-cam" is not a live-capture function, it's for post-editing only. The only way to get multi-cam live capture is with a switcher going into your NLE.

He's right......except for the last sentence. There is another way to get live multi-cam capture and I do it all the time with my old 1.5 ghz G4 powerbook so it will certainly work
on a new macbook.....but you do need to add another firewire bus with a card adaptor.
Take a look here.....
Telestream Wirecast - Overview (http://www.telestream.net/wire-cast/overview.htm)

It's made for livestreaming, but if you set the output to full resolution video and set it to record to your harddrive, you can do what you are looking to do. And yes you can switch between cameras as long as one is on a different bus (add on PC firewire card)

Big Mug Software -- Capture Magic (http://www.bigmugsoftware.com/)
Softron Media Services - MovieRecorder (http://www.softronmedia.com/products/products/mvr.html)