Pro platforms & software? Mac or PC? Final Cut, Avid, Premiere, etc.?

Question

I've a 14-year-old niece who, with iMovie, Garageband and iDVD has, in the past year overtaken her Dad's digital video camera and has produced two films (that she's finished - she has others in the works) that would be remarkable for a 40-year-old and are almost unimaginably good for a 14 (soon to be 15) year old.
Her parents and I are considering getting her the Final Cut Studio package with a Mac and enough storage space so that she can get a head start on doing what she wants to do with her life - make movies. She was able to use an older copy of Final Cut Express on a friend's father's Mac and fell in love with it - she actually understands all this stuff after just playing around with it.
Another friend's father, however, is a educated amateur and he uses Adobe products - Premier, primarily, I believe, and my niece keeps us with what's going on in Hollywood and has heard good things about products from a company called Avid and although I think that she would rather stay on a Mac platform, for certain, and she's quick to let her parents know what Hollywood films were edited, etc., on Macs ("Brokeback Mountain"? Is that true) and I think that she'd be delighted with a wicked fast Mac and the Final Cut Pro Studio package, we would like to get her a system with which she can - hopefully - be ahead of the game when it's time for her to go off to film school (if she hasn't had a major studio pick up an indie film of hers by the time she's 18!).
I know that there are companies like Sweetwater who put together and/or recommend system packages but I'm also wondering if there are video specialists that do the same? I'm also wondering if the Final Cut Studio package is actually robust enough to mix and edit a finessed final product (was "Brokeback Mountain" really edited on a Mac?) or if the Adobe products on a PC platform are more of an accepted professional 'norm'?
She already knows the camera that she wants (she shoots everything with a single camera) and the microphones, etc., that she wants for enhancing sound... BUT, although I truly believe se wants to stay on a Mac and use her iMovie, GarageBand, and iDVD skills in a more professional environment, she is being swayed a bit by her friend's evil PC-loving father.
So I need some help.
1. Is there a video resource similar too what Sweetwater is to audio?
2. Is the Mac or PC more prevalent amongst pros (or indie/beginning pros, at least)?
3. Are the Apple products superior to the Adobe and Avid products or - if they are fairly equal - is the Studio package integrated as the iLife products?
And last, I suppose, is the fact that we're thinking that Apple will be introducing the 'wicked fast' Intel desktops before Christmas so that will likely be our last purchase after we've perused the 'packaged' products (which I just assume MUST be out there!) and so while I'm glad that Apple has upgraded the Studio package to Universal binary, the choice of machines is made even more difficult by the fact that what we likely want to get or her hasn't been introduced yet.
Any answers to the three questions - or any other suggestions - will be much appreciated. It's a long time before Christmas but this is going to be an expensive venture that could well determine just how well my beloved niece will be able to fulfill her dreams.
Life was so much simpler when girls her age just wanted ponies..

Answer 1

i've been perusing Promax and have definitely settled on FCP as the software o choice and, s the camera is a 'done deal' (she knows hat she wants there!) it will ultimately come down to, I think, the CPU 'box' itself. I always think of computers as having a three-year 'window', after which time something new and exciting is blazing trails and (usually) costs have dropped (not as significantly as in the 1980's-1990's, but in terms of real dollars todays G5 Quad is a sizzling bargain compared with what I paid for my MDD Wind Tunnel G4 in 2002.
So although I would expect some of the equipment (and software - with upgrades) to remain useable for 3 years (at which time my niece will be a freshman in college) my thought at the moment is to wait until, say, October, too see if Apple is going to have blazing fast Intel machines ("MacPro" is my current guess for the name of the Intel desktops!) to go along with the Universal FCP apps. My guess is an August announcement with late September, early October shipping.
I my prognostication is wrong, however, she'll be able to 'make do' just fine with PM G5, I think. When I know a bit more about what I'm talking about (I've ordered a couple of books from Amazon to at least learn some lingo... i watched the MacBreak 1080p and compression podcasts and understood about half - when it comes to setting up a home theater, I know what to do, what i need, what to wait for, etc. But the 'broadcasting' bit is over my head (and although she may wind up in TV and need to know all that stuff, it's movies she's aiming for - yet she's realistic and says that even if she finally gets to direct a local used car commercial in her career she wants to make sure that it's the best ever!
All of this info has been tremendous - and kind of given me the impetus to begin a project started long ago (first on 8mm then 16mm... and ending just this year with miniDV!). I have a lot of iMovie footage and have burn some iDVDs but I just don't have the creative juices of my niece!