For the record, I’m having the same problem. Browser window in list view, scrollbar “hits bottom” and stops scrolling well before the actual bottom of the list, leaving numerous bins and clips unshown.
So far, if I quit FCP and start it again, I get my full browser list back (knock on wood). Annoying though. It’s a project with a fair number of clips but far, far from what I would consider “huge,” perhaps a few hundred clips in 15-20 bins…
Mac Pro 3.0Ghz / Nvidia 8800 / 10.5.2 / FCP 6.03