Re: suggestions for *lean&mean* system set-up
1) should I max out RAM? I was thinking of going for 384
If performance matters, absolutely yes. RAM doesn't cost that much, and it makes a big difference. 384 is skimpy at best--get at least 512.
3) when I crack open the box and get out the computer, should I begin (like I would with a Windows box) with reformat and OS reinstall- or do I simply uninstall the junk I don't want and go from there?
Since it'll ship with 10.3, reformatting probably isn't necessary, but if it makes you feel better (or you want to partition the hard drive) you might as well. Actually, doing an install from the OS discs and only installing the parts you want is probably a much better idea than trying to remove them--for example, all the extra language files or printer drivers can be deselected at install. Probably not a big performance difference, but saves some drive space, at least.
4) what do recommend in the case of: P2p (without spyware, needless to say), FTP, http browser (don't want to use IE), etc.?
Don't use much, but BitTorrent; either Fugu for freeware FTP or your choice of Transmit or my favorite Interarchy for more features if you don't mind paying; Safari works fine, I like Camino too (make sure to get a nightly build, though), or OmniWeb 5 if you really want the features (Mozilla Firebird isn't bad, either), and I'd just use Apple's Mail.app for mail. You wouldn't want to use IE even if it was an option--IE5 is nearly worthless.
5) what about ZoneAlarm type stuff? necessary? does MacOSX phone home and blab about what you have on your machine? what about virus prevention? I have never used it since I have cautious and unpromiscous net ways and its slows the system down so much.... but should I (these days)
The MacOS absolutely does not contact Apple other than when you first set up the computer to register, and even then only if you expressly give it permission to. OSX also has a fully-functional built-in firewall that probably works better than ZoneAlarm ever did (turn it on under Sharing). If you're exceedingly paranoid, you can use Brickhouse to set it up with even more paranoia, or just get a cheap router to abstract your computer from the Internet. Virus protection, if you ask me, is pointless right now--the anti-virus apps for the Mac all have significant reliability penalties, and there are currently ZERO non-Word-macro viruses that run on OSX. When one eventually does pop up, then buy some protection, but no sense in destabilizing your system for no good reason right now.
6) any system performance tweaks?
Get TinkerTool--it has lots of ease-of-use tweaks and a few that enhance performance. Otherwise, the less you install, the better.
No idea on #2, but good luck with your new computer.