I've been
trying this out for the last few weeks. I like it so far, and am going to keep doing it for awhile. There are a lot of little things which are nice about it, such as being able to just walk away and do something else. The way I'm set up, I'm also forced to forgo any wrist wrests and hover my hands over the keyboard and mouse, which feels much better after you get used to it.
If anyone tries this, just be aware: the first couple of days suck. Your feet and back will hurt after awhile, but you can just sit down for a couple minutes every hour or so and rest. But as with any physical activity, your body adapts. I used to do construction work, so I
know I can work while standing all day, once I get used to it.
I'm still waiting for grad school to start, so I'm not doing any real work on it yet. We'll see how it pans out when I am actually being productive.
Standing is a lost art, just like walking. That said, I spent 3 - 6 hours a day at school in arch studio, and if you do not take breaks and are not aware of how you distribute your weight, you can really cause undue stress to your hips and knees. I am still a big fan of standing, but I am mindful lest I lock my knees or put too much weight on one leg for extended periods of time.
I have been studying up a bit on how the human body works lately (been doing some boxing and martial arts stuff), and it has given me a new appreciation of how everyday bad habits can really screw you up long-term. Years of physically sedentary college and desk duty have taken their toll on me, and I never really unlearned bad habits. Little things - slouching in your chair, bad form when running, bad desk ergonomics - those add up, and may be the cause of many malaise. What I like about a standing desk is how it can force you to use your body correctly. Your body punishes you much more for pad posture, and so there is a strong feedback loop pushing you towards good habits.
Some may see a similarity to the debate about switching from QWERTY to Dvorak (or Colmak, you rapscallions!). I think this is unfair. It is much easier to switch to a standing desk, and the benefits are greater.