I pressed for a long long time to get whiteboard walls at our office. Mostly because it would be a cool/hip thing to have, and, you know, cool and hip makes you productive right?
Seriously though; it is pretty useful when brainstorming. But the BEST use is the one next to my desk where I can lean over and jot notes & progress updates etc. at will. No more post-it notes cluttering up the place :D
The other advantage over a traditional Whiteboard is the sheer size. I always run out of space on normal boards, an entire wall isn't infinite, but it takes significantly long to fill.
Some tips. This is only a "chuck it on the wall" product if you are not overly concerned with the look (for example; using it for a cafe price board etc.). In an office w/o the proper prep it can look nasty, uneven and start to get messy in very little time.
You really need to re-plaster the walls, then sand them finely (this is the big pain). And then seal them properly with a skinning under coat (that will iron out any tiny bumps). Hopefully leaving you with a nice flat surface.
We skipped this bit the first time and had to re-do the entire test wall after about 2 months.