A lot of us have been requesting this mid-range tower type option for some time, but Apple feels it would cannibalize their iMac sales on the one end or their Mac Pro sales on the other. I don't understand this concept, personally seeing as I will NOT buy either computer since the former doesn't fit my needs and the latter is beyond what I need for the price (e.g. I don't need Xeon CPUs and memory protection that jack up the price by an extra $1k). I can build a Hackintosh with at least 4-cores and a high-end GPU for around $1200 the last time I checked in a case of my choice and not have to pay exorbitant prices for ram or hard drives and put in what I want from the start.
Apple used to do it right. My PowerMac case is just a lovely piece of design in both looks and functionality. It's so easy to get into the case (no tools needed and the motherboard rotates down on a hinge from the side). They could have had quick-release sleds for the drives and what not, but it's still pretty darn easy to work on. I bought it used in '05 for $200 and upgraded the ram to 1.5GB ($80?), put in a cheap USB2 card ($25) and a flashed PC Radeon9800 Pro ($89) and a Sata card ($40) and finally a 1.8GHz 7448 G4 for $350. Oh yea and a DVD-RW 20x drive for $60. I threw in some 500GB drives I had lying around from another computer (I eventually replaced them with two 1.5TB Barracudas some time later). I could have had a Mac-Mini at the time instead, but all drive expansion to that level would have had to be external and I don't think the 2006 Mini was very good at all (32-bit Intel CPU, slow DVD drive, no FW 800, Intel graphics that was probably at least as slow as the 9800 Pro if not more so, etc. and in 2005, they were still selling the MacMini G4).
I'm STILL using that PowerMac today as a whole house audio/video server (for multiple ATVs and Airport Express units) and 24/7 Internet terminal and quick'n'easy label maker, document reader, etc. (since it's on 24/7, it's very convenient to just turn on the monitor), although now I use external 3TB USB3 storage that will be easily moved to another computer in the future. I doubt I would still be using a 2005 or 2006 Mac Mini and the '06 model will not have Lion support either.
I've easily upgraded the monitor to a 22" LCD and have since added a 20" HDTV/Monitor so I can watch the news while reading e-mail and yet easily have a two monitor setup if I want at the push of a button (9800 Pro makes that possible; the 2005/06 Mac Mini only had one output). I can also play older PPC games on it and even OS9 ones with a reboot. I've actually played everything from Halo to No One Lives Forever 2, Jedi Academy, ProPinball (in OS9) to Diablo II to old Lucasfilm games and Roller Coaster Tycoon 3 on it (not bad for an ancient machine made in 2001).
And before someone complains about 'speed', I'll say that it feels just as fast as my 2008 MBP for most daily operations (typical browsing sites, e-mail, etc. and '04 Office feels the same on the PowerMac as it does under Rosetta on the MBP. Photoshop CS3 feels fine, etc. XBench measurements show that the 2001 PowerMac in question runs significantly FASTER in nearly all areas than the Dell Mini10V Netbook I bought in 2010. Yes, it's a Netbook, but it's still made to be used in 2010 so the PowerMac still holds its own. Yes, the PowerMac had upgrades done to it, but that's my whole point about an expandable computer over a disposable one. Sadly, even the Mac Pro is becoming disposable with newer GPU cards often not being compatible with older models, etc.
Show me a Mac made today that will have a 10+ year shelf life like that....
And the only thing that is going to force me to upgrade is the lack of software support for PPC (from browsers to utilities, they're all dumping it now and that is a direct result of Apple dumping PPC from XCode4 and little else). Otherwise, I'm sure I'd get at least another 2 years out of it. As long as I can get updates to iTunes and at least one major browser, it may still go another two years.
Oh yeah, it was also Made In the USA (power supply has been running 24/7 since about 2006 save vacations, etc. and it's holding up like a champ).