I often use FireFox for editing on Wikipedia; thusly, I go up my watchlist, opening up dozens of tabs. I then go through them all. All this time, my internet usage is minimal, and my watchlist is increasingly stale. It would be nice if an option to add an autorefresh tage to watchlists were possible; I do not think this will be a bandwidth problem as watchlists are not large pages,
and they would only need to be refreshed every tens of minutes, and most users will never leave a watchlist open that long regardless.