Not realistic.
...speaking as someone who has both used, and has observed others using, the pedestrian desk type of system.
GSK's staff doesn't use them anywhere NEAR as much as you'd think.. it's hard to do any sort of productive work when your gait makes it difficult to focus on a computer screen, or writing.. typing is viable, but writing is generally out of the question.
Another entity I've seen that uses them is the Educational Credit Management Corporation - ECMC is one of the major education loan processors in the country. There, pretty much anyone who has a walking desk also has a sitting desk as well.
Neat idea, but not 100% viable across the board yet.
