Built from the ground up and as a successor to the PowerMac, the Mac Pro continues Apple's tradition of offering the speed and performance the professional desktop user demands but most importantly, requires.  Note that the MacPro can be much more than the average non-professional would ever need.  Therefore, unless you're working in one of the above mentioned fields, the Mac Pro may be too much to bite into.  Your wallet will be better served by the iMac or the Mac mini.

Outside of an 8-core model addition in April 2007, the Mac Pro is now on it's third product cycle, or in other words, it's second revision.  The following is a list of the Mac Pro release dates:

• Original Release: August 7, 2006
• Update - April 4, 2007, 8-core system added
  
• Early 2008 - January 8, 2008 - Intel "Penryn" Xeon processors
• Early 2009 - March 3, 2009 - Intel "Nehalem" Xeon processors
  

In the Box

Design - Don't Let the Aluminum Case Fool You
At first glance, the Mac Pro case with it's exposed ports on the front and back looks like a simple machine.  Don't be fooled because behind that beautiful aluminum case sits one of the most powerful workstations money can buy.  Built around the latest and most capable Intel "Nehalem" Xeon Processors, the 64-bit architecture and 8MB of fully shared L3 cache in conjunction with a new system architecture that leverages the Nehalem's integrated memory controller and support for Hyper-Threading makes these systems fly.  On top of that, the workstation graphics, PCI Express 2.0, storage capacity, optional dual optical drives, ports, expansion slots, and expansion options, allow the Mac Pro to be configured to meet just about any professional demands by offering millions of possible configurations.  The design offers owners the ability to easily expand the machine as usage requirements change or expand.

The Ultimate Desktop Mac - 8 cores or 4 cores
The Mac Pro can be configured with up to two Quad-Core Intel Xeon "Nehalem" processors running up to 2.93GHz giving the system groundbreaking 8-core power.  These are the fastest quad-core Xeon processors available from Intel.  The standard configuration ships with a 2.66GHz Quad-Core Intel Xeon processor.  Regardless of the configuration, the Mac Pro will deliver advanced performance.

8-core Mac Pro processor options:

• Two 2.26GHz, 2.66GHz, or 2.93GHz Quad-Core Intel Xeon "Nehalem" processors with 8MB shared L3 cache per processor (5500 series processor)
• Next-generation Intel microarchitecture
  

Quad-core Mac Pro processor options:

• One 2.66GHz or 2.93GHz Quad-Core Intel Xeon "Nehalem" processor with 8MB shared L3 cache (3500 series processor)
• Next-generation Intel microarchitecture
  

Architecture and noteworthy features of the Mac Pro:

• 8MB of L3 cache per processor
  
• Integrated memory controller
• Turbo Boost dynamic performance
• Hyper-Threading technology - virtual cores
• 128-bit SSE4 SIMD engine
• 64-bit data paths and registers
• Four 3.5-inch hard-drive bays - supporting up to 4TB of internal storage
• Double-wide, 16-lane PCI Express 2.0 graphics slot
• 1066MHz DDR3 ECC SDRAM
• Eight memory slots supporting up to 32GB of main memory on the 8-core model
  
• Four memory slots supporting up to 8GB of main memory on the Quad-core model
• One PCI Express 2.0 ×16 slot
• Two PCI Express 2.0 ×4 slots
• Optional dual 18x SuperDrive with double-layer support (DVD±R DL/DVD±RW/CD-RW)
• Four FireWire 800 ports, two each on the front and back
  
• Five USB 2.0 ports, two on the front, three on the back
  
• Front-panel headphone minijack
• Internal speaker
• Optical digital audio input and output TOSLINK ports
• Analog stereo line-level input and output minijacks
• Support for multiple displays
• Multiple graphics card configurations support

Apple LED Cinema Displays are a Perfect Match
Unlike the iMac but similar to the Mac mini, the Mac Pro doesn't come with a display.  That's solved by connecting an optional widescreen Apple LED Cinema Display.  A perfect compliment to the Mac Pro, the displays feature the same anodized aluminum enclosure found on the Mac Pro.  The two look great side-by-side and can be the envy of any computer user.  The shipped graphics card in each Mac Pro supports dual displays.  If that's not enough, you can configure your Mac Pro with up to  four graphics cards  thereby giving you support for up to eight displays.

What Can you do with a Mac Pro?
Simply put, just about everything.  The Mac Pro can do almost everything an iMac can do but more.  Note that the Mac Pro doesn't have a built-in iSight camera as found on the iMac, MacBook Pro, and MacBook so you won't be able to video conference out-of-the box.  That's solved by purchasing an external iSight camera.  Mac users can use the full range of Apple software from the built-in applications that ship with Mac OS X to the most demanding titles such as Final Cut Pro, Shake, Aperture, and Logic Pro.  The most demanding third-party software for professional use will run like a charm on a Mac Pro.

Conclusion & Buying Advice
Geared towards professionals, the Mac Pro is the ultimate desktop Mac workstation.   Unless you need the features offered by the Mac Pro such as  Quad-core or 8-core processing,  PCI Express, multiple graphics card support, and a large amount of RAM, you're better off settling for an iMac.  But hey, don't let this article discourage you.   If you want the ultimate desktop offered by Apple, have the extra cash lying around, or wanna brag to your friends that you have the ultimate Mac, get the Mac Pro.

Updates

• April 9, 2009 - Updated content for new Nehalem models released in March 2009, updated images
• January 8, 2008 - Updated information about new Penryn based systems and content revision
• April 4, 2007 - Added information about 8-core Mac Pro and content revision