I hate it when people are hating on my baby!
Look, my MP 1,1 still runs circles around my daughter's 1 year old MBP. I've got two large non-glossy screens hooked up to it and could connect two more if wanted to -- try doing that with an iMac. With 12GB of RAM, I can run Fusion without worrying about mac apps grinding to a halt because of insufficient RAM allocation (and I keep at least a half dozen running while I'm doing Windows). I have plenty of cheap storage, including external eSata drives, and I can now add USB 3 drives if I so choose (good luck getting anything faster than FW800 on the iMac!). I have absolutely no issues with the 4870 video card, but then again I have no need or desire to render HD video or play the latest shooter game at 300 fps (30 fps is fast enough to fool me into believing I'm seeing totally fluid motion). If you're into games, go build yourself a PC gaming rig. If you make money in video, yeah, get yourself the newest 12 core MP. For anything else, MP 1,1 is more than good enough. Sure, I can afford to replace my MP 1,1 with the newest MP, but frankly I don't see or feel the need to, given what I use it for (multitasking, photography, running productivity apps under Fusion, playing an occasional game). I'd rather go get myself another lens.
If I had only $2000 to spend, I'd buy a used MP 1,1, put in at least 8GB of RAM in it, a couple 2 TB drives, and I'd round it all out with a refurbished 16GB iPad for those times I feed like reading Macrumors on the toilet.