We have machines scattered throughout the office for meetings (mostly Jira or other web applications). One of those has Haiku running and people seem to like it just fine.
I do find, however, the ergonomics of the window manager to be atrocious. The little tabs, while faithful and part of the visual identity of BeOS, are, perhaps, the worst idea since the invention of overlapping windows. I'd suggest focusing on the 80's icon style and 45° perspective as visual identify and ditch the title tabs.
Protip (sorry for using the term), stop using the titlebar to move Windows. I feel physically encumbered when using Windows or OS X because I can't Alt+Drag windows around. It will make you so much faster because you just hold Alt and click and drag. No more searching for that tiny little microscopic bit of window to drag. (For example, Chrome on OS X has almost NO hit space to drag the window). I guess this post is sorta useless if you don't use Linux, but take it for what it's worth I guess.
I can't bring myself to do that on a 15.4" screen (I like the real estate specifically for multitasking and looking back and forth) but I've seen it leveraged extremely well on a 11/13" Air.
I do find, however, the ergonomics of the window manager to be atrocious. The little tabs, while faithful and part of the visual identity of BeOS, are, perhaps, the worst idea since the invention of overlapping windows. I'd suggest focusing on the 80's icon style and 45° perspective as visual identify and ditch the title tabs.