i'm not going to bash you just offer you some friendly advice....listen carefully. i work at a huge marketing agency in the digital marketing division. we specialize in broadcast 3d and digital effects production. before i arrived there, to my surprise all the artists were using macs! now i can understand the print creatives using macs since printers are calibrated with mac calibrations and most of them are mac dorks to begin with, but for doing 3D work?????? NO! The people in my department thought I was crazy for thinking a mere PC could outshine their precious babies. I was sick and tired of fighting a losing battle so I convinced one guy in my department to let me build him a PC. For less than $2,500 I built him a system with the following specs:
Athlon Thunderbird 1.2MHz (266fsb) (overclocked to 1435MHz)!!!
768 MB Kingmax PC150 SDRAM
30 GB IBM Deskstar 75GXP Ultra ATA/100 HD
Elsa Gladiac Ultra 64MB DDR
12x cd-writer
dvd drive
250MB internal zip
AWESOME case with GREAT cooling
19" Sony G400 Flat Monitor
and all the trimmings
I quickly put it to the test, first running a battery of benchmarks
1) 3D Mark 2000 - tests the graphics card's performance in gaming situations
2) Spec Viewperf 6.1.2 - Tests the OpenGL of the card in real life simulations of various high end programs
3) Cinebench 2000 - Tests the OpenGL of cinema 4DXL and the OpenGL of the graphics card and the speed of rendering. Great test as Cinema uses less than 2% of system resources.
4) Video compression - we compressed a video using quicktime 4.0 and sorenson 2.0 compression and timed the test
5) Photoshop - We ran a battery of Filter tests...I let him choose the filters and we had the 2 computers next to each other and hit apply at the same time and timed the results.
EVERY test we performed the PC SMOKED his G4 500....even the Quicktime test which is optimized for G4 velocity engine. None of this shocked me at all but needless to say these tests raised a few eyebrows. I mean some of the tests were like 4-10x faster on the PC...it was pathetic! I'm tired of MAC elitists trying to pawn their propoganda off on the uneducated consumer as something to be held on a pedastal and admired. Sure the boxes look nice and they are relatively easy almost insultingly easy at times to work with, but the mac users i know use this aura of elitism to sheild them from the truth. None of them know a damn thing about hardware and believe everything apple tells them about the power and value of their machines and it's all BS. My buddy's mac crashes AT LEAST three times a day...oops......i forgot to restart my windows 2000 machine last month......get my point? Do yourself a favor...don't wait for Maya to come to OSX....you'll be waiting for at least 6 months....then it has to be proven and tested and debugged for another year or two. Build yourself an NT box for 3 grand and then with the money you saved by not getting a "comparable" mac go on vacation and relax.......again, this is not meant as a personal diss to you or any other mac user. i understand why some people buy into the mac ideology and culture, but if you want to really work, especially in 3D, it only makes sense to build a PC. This is of course my opinion, but i believe it to be an educated one. I have been researching and benchmarking all sorts of configurations of systems for some time. don't underestimate the pc......too many mac users equate the pc with microsoft and they hate microsoft for ripping the mac os off.....you think i give two sh*ts about bill gates and microsoft? hell no! but i know what it takes to get work done. If you want to waste your money even more buy an sgi machine....the new octanes are only about $50,000. crap, if you could drive the thing to work then maybe i'd get one too, but until then....
good luck!
p.s. i get a little hot headed at times but i speak honestly, don't take it personally! 
Windows 2000
Abit KT7 non-raid
Duron 700@1000
Elsa Gladiac Ultra 64MB DDR
512 MB Corsair SDRAM
21" Sony F500
3DMARK 2000 = 7104