I've read that we can install a Windows OS on Intel-based Apple.
Does that mean we can install MC on a Mac? And use our regular VST plug-ins?
Since there are multiple ways of running windows on a intel mac, the answer is, it depends.
If you dual boot the machine (ala boot camp) there are 2 separate OS's running on it so in that case you'd run MC in windows and it would be like any other windows box.
If you ran parallels (I haven't tried this) you supposedly can run MC in a windows window in the osx desktop.
I have tried running in a windows container in virtualbox on a mac, that works fine for me since I'm mostly using the server features of MC that way. You won't be able to do any 3d visualizations that way however.
Would MC communicate with Firewire Mac-only devices?
Depends on which method you are using. If you are dual booting, probably yes. The exception would be HFS (the mac filesystem) formatted ipods. The windows OS can't access the HFS filesystem without 3rd party apps.