It was replaced 3 years ago in my home office by a 27" iMac (I had about a $3500 credit with Apple, and after looking at what the new Mac Pro offered, I decided instead to deck out an iMac with every possible upgrade and feature — still a screamer).
As for the Mac Pro, it moved into my office at work. Every other year, my work plops a new iMac on my desk. They buy bottom-of-the-barrel, so it's always a 21" with the bare minimum of RAM, processor, and probably most importantly, a 5200 rpm spinning platter. Even on the first day, those iMacs are dog slow (probably doesn't help that they come with all sorts of IT-installed nannyware, which I immediately wipe clean). Don't get me wrong, I love iMacs (after all, I turned down a nMP 3 years ago to get an iMac instead). But someone at Apple needs to be terminated (in a swamp) for what they sell at the bottom end of the iMac line.
But my Mac Pro, 10 frickin years old, will run circles around those institution-provided machines. Over the years, it's been upgraded with a new video cards, more RAM, 8-core X5365 processors, and an SSD boot drive. It's a joy to use! Because it has so much internal storage, I use it to store all the many recordings I make in my classes (which it chomps through in FCX just great). In day-to-day use for the tasks that I do, my impression of it is comparable with my i7 iMac — and soooo much better than the junk iMacs the workplace buys. And frankly, it's fun to have a Mac you can still tinker with (what little tinkering is required on my part up until this point to get the latest OS X running, thanks to the geniuses on this board).
Every time a new iMac appears on my desk, I generally find a junior faculty member who would prefer to have a Mac in his/her office and I "re-home" it.
Here's a recent photo, the iMac pictured is now living life on the desk of one of our new hires who got saddled with a junky PC laptop when he first arrived.
